GTA
All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Topic started by: Nomadic Pirate on January 30, 2021, 07:08:51 PM
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I scored this very High quality 3/4" particle board.
This stuff is really dense, really heavy and hard to cut with a circular saw
I don't know if it's any harder to penetrate then a quality 3/4" Birch ply but it's definitely gonna be more uniform by nature.
This test I will shoot 2 of each 200gr .357 Western Bullets, 190gr .357 Hunter supply, 148gr .357 Hollowpoint Matt's bullets, 120gr .357 Hollowpoint Rick Merrell, 81gr .357 JSB, 81gr .357 Polymag
I also will shoot for comparison 51gr .30 JSB and 34gr .25 JSB to see what kind of difference we'll get compared to the .357s
I will shoot all the .357 out of my REX Carbine that gets 180 FPE with the 200gr
I will refill the REX after each 2 shots that I take.
The .30 will be shot with a 90 FPE gun and the .25 with a 65 FPE gun.
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Forgot to mention,
I will then alternate several layers of alternating thick carboard and 1/4" Birch Plywood.
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8 sheets of 1/4" ply are cut
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And the target face has been mapped,
Trying to keep at least 4" between the shots to minimize any possible disruption
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That looks like MDF to me, not particle.
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Nice, that board looks too purty to shoot? I'll be following.
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Woohoo, I'm guessing that at 20 yards, everything but the Polymag will jet right through...
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That looks like MDF to me, not particle.
What is MDF ?
I just figured was some kind of super dense Particle board.
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Medium density fiberboard. Finer particles than particleboard...basically dust bound together.
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Medium-density fibreboard
https://en.wikipedia.org/wiki/Medium-density_fibreboard
I see you live in Hawaii. That's where I'm from. Moved to Texas several times in the 80's and 90's, and been here since 93 or 94. I'm from Waipahu
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Test seems quite scientifically structured to eliminate whatever variables you can.
But exactly how are you gonna measure penetration depth (or anything else) with that tape measure? Belongs in a museum! ;D
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Woohoo, I'm guessing that at 20 yards, everything but the Polymag will jet right through...
Ya think ? :)
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Medium-density fibreboard
https://en.wikipedia.org/wiki/Medium-density_fibreboard
I see you live in Hawaii. That's where I'm from. Moved to Texas several times in the 80's and 90's, and been here since 93 or 94. I'm from Waipahu
Cool, thanks for the link.
so not only it's more consistent then Ply, but looks like it's stronger too.
Should be perfect for this test and other tests too,....I have more to take from work as well
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OK, so I finished my test target :
MDF board, then 2 layers of thick cardboard,
After that alternate layers of eight 1/4" ply and thick carboard
and last a 3/4" Ply to complete the test target.
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Yep, that's MDF, and I'll also note, a darn good testing medium! That's what I use to determine if a gun has the snuff to poke though a skull. That MDF is really dense, and consistent, so should be great for repeatable tests. The only warning I'll have is, don't put shots too close to each other. Try and keep them at least 2" apart, because the exit will blow out a larger piece of wood on that MDF. This should be interesting! Smythsg is probably right. Everything will probably poke through that MDF, with the exception of the 65 fpe .25, maybe...
The real question is gonna be how far the projectiles make it after that MDF, because it will cause expansion :D
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Watching; this will be great :D-that mdf is no weak stuff; I will be very surprised if there are any pass throughs, personally. Though I do expect to see some very nasty looking "wound" cavities...
Jesse
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Yep, that's MDF, and I'll also note, a darn good testing medium! That's what I use to determine if a gun has the snuff to poke though a skull. That MDF is really dense, and consistent, so should be great for repeatable tests. The only warning I'll have is, don't put shots too close to each other. Try and keep them at least 2" apart, because the exit will blow out a larger piece of wood on that MDF. This should be interesting! Smythsg is probably right. Everything will probably poke through that MDF, with the exception of the 65 fpe .25, maybe...
The real question is gonna be how far the projectiles make it after that MDF, because it will cause expansion :D
Cool, I'm excited now and I have more of this stuff I can swipe from work for future testing
always been looking for a medium that is consistent and uniform for accurate comparison
All shots will be a bout 4" apart exactly for that reason, also the clamped layers at the back should minimize expansion and damage to the back of the board,.....I guess ? :) :)
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Watching; this will be great :D-that mdf is no weak stuff; I will be very surprised if there are any pass throughs, personally. Though I do expect to see some very nasty looking "wound" cavities...
Jesse
Yeah, I don't expect anything to go through all that layering
It will be interesting to check the damage and distance traveled into the system.
This time I will do a post for every pellet/bullet recovered with distance and pictures otherwise it gets to confusing to do the report all together.
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Nice test.
The tape measure is just getting broke-in.
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This should work very well! I'm really looking forward to seeing the results on it, because I've wanted to do a very similar test to test ultimate penetration after the 3/4 MDF. I just haven't gotten around to it :( This should be a PERFECT penetration test me thinks.
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Yeah, I think to have a uniform initial board is the key,
The layering of thick carboard and thin plywood should work very well to give projectiles some resistance after blowing through the MDF and should give a good read of further travel
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I've never shot MDF but I use scrap 3/4 plywood to stop pellets when I am getting velocity readings on my 25 caliber Avenger. It blows through it with the regulator set to 1500 psi. fpe is 33 to 39 depending on the pellet weight. Velocity goes from a little over 700 fps to over 850 depending on pellet mass. I have a second piece behind the first and it just gets dented typically. I will turn up the regulator eventually but I am having fun with it at the low regulator setting. It can be raised as high as 2900 psi on this rifle.
My main hobby is woodworking. I don't like MDF because the dust it makes is terribly nasty. It is not stronger than plywood, it is weaker. It is also easily damaged by water. The Brits talk about water resistant MDF but I've never seen it. For shelving purposes we look at the modulus of elasticity. Hardwood is strongest, has the highest modulus, softwood is next, then plywood, then particle board, then MDF. I don't know however, if that translates to penetration but I tend to think it does. If I had any laying around I would shoot it and find out. I agree, however, that MDF will be more consistent than wood or even plywood. Shooting it may be a good thing to do with MDF.
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Stage is set, time to start shooting ;D ;D
I don't think any will but just in case I put a foam board behind the target to catch any possible pass through.
This sucker is HEAAAVY ;D ;D ;D must be 60 + pounds
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All shooting done !
As expected nothing came out da back,
time to go gather some data ;D
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Here is how the back of the MDF looks, can see that the .30 and .25 didn't make it through.
And on the immediate cardboard backing you can see some nice expansion on the Hollowpoints.
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I've never shot MDF but I use scrap 3/4 plywood to stop pellets when I am getting velocity readings on my 25 caliber Avenger. It blows through it with the regulator set to 1500 psi. fpe is 33 to 39 depending on the pellet weight. Velocity goes from a little over 700 fps to over 850 depending on pellet mass. I have a second piece behind the first and it just gets dented typically. I will turn up the regulator eventually but I am having fun with it at the low regulator setting. It can be raised as high as 2900 psi on this rifle.
My main hobby is woodworking. I don't like MDF because the dust it makes is terribly nasty. It is not stronger than plywood, it is weaker. It is also easily damaged by water. The Brits talk about water resistant MDF but I've never seen it. For shelving purposes we look at the modulus of elasticity. Hardwood is strongest, has the highest modulus, softwood is next, then plywood, then particle board, then MDF. I don't know however, if that translates to penetration but I tend to think it does. If I had any laying around I would shoot it and find out. I agree, however, that MDF will be more consistent than wood or even plywood. Shooting it may be a good thing to do with MDF.
Well data says the opposite :) :)
My .25 and .30 Blow through quality 3/4" Birch Plywood and keep going for some time into other mediums, both didn't even make it out of the MDF :)
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120gr Rick Merrell
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148gr Matt's bullets
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Predators
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JSB .357
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.30
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.25
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So only the 200gr and 190gr made it past the 1st Ply
let's go see how far they made it ;D
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The 1st 190gr was found resting in the cardboard behind the 1st ply
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the 2nd 190gr was found stuck into the 2nd ply with the 1st 200gr resting in the cardboard behind it
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The other 200gr went through the 3rd Ply and was resting in the Cardboard behind it
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I've never seen this kind of expansion on the 190gr bullets
this 3/4" MDF is way stronger then quality 3/4" Plywood
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I still struggle to call MDF strong. If you want to know why try making a shelf out of it. But it is more dense, it weighs more per unit volume. Maybe that is what counts for penetration. The weight comes from all the glue holding the wood dust together. A sheet of 3/4 plywood is about 75 lbs, a sheet of MDF (medium density) is about 90 lbs. So perhaps the density makes it harder to penetrate.
It appears weight of the projectile has a lot to do with penetration.
I like testing in wet paper, ideally newsprint. Due to availability I plan a test in glossy paper - magazines and catalogs. I only had 4 inches for my last test and some of my 22 pellets make it through - at less than 20fpe. I plan to use at least 6 inches to test my 25 caliber Avenger. I'd like to have 8 inches or more.
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If that was a 3/4" Ply the high weigh bullets probably would have made it all the way.
this 3/4" MDF might not be structurally stronger but it surely is way, way harder to penetrate then quality 3/4" Birch ply
real world testing don't lie :)
It's to strong to make any meaningful penetration testing, from now on I will only use it as security backstop.
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Here is how the back of the MDF looks, can see that the .30 and .25 didn't make it through.
And on the immediate cardboard backing you can see some nice expansion on the Hollowpoints.
AWESOME! I was very close on my guess :D I kinda thought the .30 may not make it through, but I hedged my bets and just said the .25 wouldn't,lol! Your results are very useful for people trying to understand real penetration. I suspect you may get different results if you swap out the .30 and .25 with slugs. I'm assuming you're shooting the .25 at 65 fpe, and what was the .30 at 70 or 85 fpe? I was assuming the .30 was the 80 fpe.
That MDF is just so dense, it'll make almost anything expand. It takes some good power to poke through a 3/4" sheet of it. You're making me want to get off my rear, and test my .22 and .177, while I have them set up for their high power hunting tunes... I know they'll poke through the MDF, but the after part is what I'm curious about?
Great job on the test Manny!!!
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Thanks,
the .30 is at 90 FPE
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Well, I have a lot of untouched left over material for more testing ;D ;D LOL
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About MDF VS Plywood:
Penetration is not just blocked by strong materials, but by heavy ones that generate a "friction cone" once penetration starts. Think about how effective sand is at stopping projectiles - and it has negligible bulk strength. Only mass and friction.
The nature of MDF fiber is to form an expanding cone in front of a penetrating projectile. The the deeper the projectile penetrates, the greater the mass of material the projectile has to push ahead of itself, in a much greater than linear progression. Ditto for the total area that sees friction within the material. Hence MDF is harder to penetrate than plywood, despite being weaker when "bend tested".
Mass can also aid penetration of strong materials:
Think of shooting at a 1" steel disc that is only .02" thick (like a thin steel coin, if you will), using an airgun projectile travelling at 800 FPS. Those discs are so light that they are thrown out of the way, rather than penetrated, if you stick just one edge lightly into clay. Now, back that same little "coin" fully with a pound of clay so it can't move easily, and see how easy it is to penetrate.
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Well, I have a lot of untouched left over material for more testing ;D ;D LOL
Do it with slugs in the .25 and .30! I'm curious to see if they'll make it through. I suspect they will, but I could be wrong?
About MDF VS Plywood:
Penetration is not just blocked by strong materials, but by heavy ones that generate a "friction cone" once penetration starts. Think about how effective sand is at stopping projectiles - and it has negligible bulk strength. Only mass and friction.
The nature of MDF fiber is to form an expanding cone in front of a penetrating projectile. The the deeper the projectile penetrates, the greater the mass of material the projectile has to push ahead of itself, in a much greater than linear progression. Ditto for the total area that sees friction within the material. Hence MDY is harder to penetrate than plywood, despite being weaker when "bend tested".
Mass can also aid penetration of strong materials:
Think of shooting at a 1" steel disc that is only .02" thick (like a thin steel coin, if you will), using an airgun projectile travelling at 800 FPS. Those discs are so light that they are thrown out of the way, rather than penetrated, if you stick just one edge lightly into clay. Now, back that same little "coin" fully with a pound of clay so it can't move easily, and see how easy it is to penetrate.
Makes perfect sense!
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OK, I'm gonna try shoot .30 and .25 slugs,......my bet, they aren't gonna get through :)
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OK, I'm gonna try shoot .30 and .25 slugs,......my bet, they aren't gonna get through :)
They might, if they are "solids"...
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OK, I'm gonna try shoot .30 and .25 slugs,......my bet, they aren't gonna get through :)
They might, if they are "solids"...
Yes I have solids both in .25 and .30
But going by How little penetration 200gr and 190gr solid slug had I guess not :)
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Test seems quite scientifically structured to eliminate whatever variables you can.
But exactly how are you gonna measure penetration depth (or anything else) with that tape measure? Belongs in a museum! ;D
You could just poke a section of rod or coat hanger into the hole. Mark what’s flush. Measure between Mark and tip.
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That tells you how deep the projectile base is; but not how deep the nose is...
Test seems quite scientifically structured to eliminate whatever variables you can.
But exactly how are you gonna measure penetration depth (or anything else) with that tape measure? Belongs in a museum! ;D
You could just poke a section of rod or coat hanger into the hole. Mark what’s flush. Measure between Mark and tip.
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Yes I have solids both in .25 and .30
But going by How little penetration 200gr and 190gr solid slug had I guess not :)
Round nose, heavy for caliber .25 and .30 should do well. Especially if made from lead with 3+% antimony.
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Fascinating, at first I did not think you could differentiate penetration depths because of the density of MDF. But brittleness and being less resistive to flex proved otherwise.
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I've never shot MDF but I use scrap 3/4 plywood to stop pellets when I am getting velocity readings on my 25 caliber Avenger. It blows through it with the regulator set to 1500 psi. fpe is 33 to 39 depending on the pellet weight. Velocity goes from a little over 700 fps to over 850 depending on pellet mass. I have a second piece behind the first and it just gets dented typically. I will turn up the regulator eventually but I am having fun with it at the low regulator setting. It can be raised as high as 2900 psi on this rifle.
My main hobby is woodworking. I don't like MDF because the dust it makes is terribly nasty. It is not stronger than plywood, it is weaker. It is also easily damaged by water. The Brits talk about water resistant MDF but I've never seen it. For shelving purposes we look at the modulus of elasticity. Hardwood is strongest, has the highest modulus, softwood is next, then plywood, then particle board, then MDF. I don't know however, if that translates to penetration but I tend to think it does. If I had any laying around I would shoot it and find out. I agree, however, that MDF will be more consistent than wood or even plywood. Shooting it may be a good thing to do with MDF.
That’s what I was thinking. Go ahead and shoot it. Sounds like an awesome penetration test.
But as far as a building material? Is Hawaii humid? Wherever MDF was used. Check back in a few years and see where it’s bubbling and coming apart.
Both the wood dust and the binding agent seem to absorb up water.
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That tells you how deep the projectile base is; but not how deep the nose is...
Test seems quite scientifically structured to eliminate whatever variables you can.
But exactly how are you gonna measure penetration depth (or anything else) with that tape measure? Belongs in a museum! ;D
You could just poke a section of rod or coat hanger into the hole. Mark what’s flush. Measure between Mark and tip.
True. But we know the projectile won’t be any longer than new. So you have a good enough measurement.
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True. But we know the projectile won’t be any longer than new. So you have a good enough measurement.
Don't lose sight of the point of this exercise: If we want to be sure that a projectile has passed through an animal's skull, we want to know where the projectile's nose stopped, not its base.
All moot, if the projectile base makes it all the way through.
It is all a matter of how "good enough" is defined. To me, good enough means the projectile impacts the far-side of the skull, after blowing through the nearside. So, measuring partial penetration of a wood substitute, used as a bone substitute is a little dicey.
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I've never shot MDF but I use scrap 3/4 plywood to stop pellets when I am getting velocity readings on my 25 caliber Avenger. It blows through it with the regulator set to 1500 psi. fpe is 33 to 39 depending on the pellet weight. Velocity goes from a little over 700 fps to over 850 depending on pellet mass. I have a second piece behind the first and it just gets dented typically. I will turn up the regulator eventually but I am having fun with it at the low regulator setting. It can be raised as high as 2900 psi on this rifle.
My main hobby is woodworking. I don't like MDF because the dust it makes is terribly nasty. It is not stronger than plywood, it is weaker. It is also easily damaged by water. The Brits talk about water resistant MDF but I've never seen it. For shelving purposes we look at the modulus of elasticity. Hardwood is strongest, has the highest modulus, softwood is next, then plywood, then particle board, then MDF. I don't know however, if that translates to penetration but I tend to think it does. If I had any laying around I would shoot it and find out. I agree, however, that MDF will be more consistent than wood or even plywood. Shooting it may be a good thing to do with MDF.
Well data says the opposite :) :)
My .25 and .30 Blow through quality 3/4" Birch Plywood and keep going for some time into other mediums, both didn't even make it out of the MDF :)
That would make sense. It’s dense. And it isn’t connected through the grain like real wood.
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One more point I like to make :
I'm quite confident if the MDF board was standing alone all projectiles would have made it through, but having those layers pressed behind the board is an all different cup of tea since they offer a lot of resistance so it's much harder to blow to the other side.
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It’s a cool test.
I think all projectiles would penetrate a skull, depending on angle of impact more or less.
If I ever get to pop the skull of the animal I PMd you about, I’ll let you know.
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It’s a cool test.
I think all projectiles would penetrate a skull, depending on angle of impact more or less.
If I ever get to pop the skull of the animal I PMd you about, I’ll let you know.
Of course they will ALL penetrate the skull of a big game animal that has been confirmed and re-confirmed many a time,
but that was not the goal of the exercise, the goal was to see the difference between the .357 ammo,...the .30 and .25 where just thrown in for kicks :)
Unfortunately the MDF board proved to strong and there was no real separation,.....I will probably repeat the same test without the MDF
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Very interesting results Manny! Now I have to get me some 3/4 MDF to test with my Condor and my Escape. I can crank up the fpe with those two and see if I can penetrate. I don't remember seeing it, but I assume you were shooting at 20 yards?
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Correct.
Today I will take some shots with the .25 at the board standing alone and I'll predict easy blow out da back :)
The compressing of layers at the back of the board makes a world of difference.
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Stand alone MDF
took 3 shots with the .25, same pellet and same gun as yesterday
blown through ;D
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Look forward to your results. Hopefully I can get to Lowes tomorrow to pick up a piece of MDF.
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Wow, you posted results as I was posting a reply... ;D Now that we know the .25 penetrated all the way through at 20 yards, I will move out to 35 yards and shoot mine with the Condor at 65 fpe. I will be shooting NSA 33.5 gn slugs.
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Dang! A lot to be said for a heavy slug moving slow; 180 FPE and a 200 grainer is what; 600-ish FPS?
Put a whole lotta hurt on whatever it hits; that's for sure. :o
Watching for edition 2, thanks for the results,
Jesse
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Manny, may I suggest spacing the MDF an inch or so apart from the cardboard stack, that will allow a more fluid flow of the simulated skull materiel and still have a good indication of continued pellet path.
Interesting testing so far BTW !
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Manny, may I suggest spacing the MDF an inch or so apart from the cardboard stack, that will allow a more fluid flow of the simulated skull materiel and still have a good indication of continued pellet path.
Brilliantly simple and effective suggestion. Could make the spacing just a little more to ensure the MDF divot does not get in the way of the projectile impacting the thin plywood and cardboard medium.
I presume the point of the backing layers is to get some idea of the remaining damage potential. Something that one could measure with a chronograph, if you don't mind risking it :). However, the mangled projectile is best caught, so one can evaluate its shape and remaining weight.
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Good stuff!
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Manny, may I suggest spacing the MDF an inch or so apart from the cardboard stack, that will allow a more fluid flow of the simulated skull materiel and still have a good indication of continued pellet path.
Brilliantly simple and effective suggestion. Could make the spacing just a little more to ensure the MDF divot does not get in the way of the projectile impacting the thin plywood and cardboard medium.
I presume the point of the backing layers is to get some idea of the remaining damage potential.
Yes, yes and yes
But the 3/4" MDF has proven just to strong to aloud meaningful travel into other layers, I think 1/4" or 3/8" would probably be much better.
I will revert back to quality ply as my face for test targets, it might not have the uniform consistency of MDF but that is also why I usually shoot 2 rounds of each to get the average,.....3/4" quality ply already exceeds the requirement for skull strength.
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What I'm gonna use the MDF from now on is to check the cone produced by the different rounds on a stand alone board with 8-10" behind several layers of cardboard screwed to a 3/4" ply to catch the bullet/pellet.
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Unfortunately I will not be able to do testing with the 3/4 MDF as both Lowes and Home Depot will only sell the stuff in a 4x8 sheet for just less than $40.00 a sheet. A bit too rich for me to blow a few holes in, so like Manny, I will go back to the ply.
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Unfortunately I will not be able to do testing with the 3/4 MDF as both Lowes and Home Depot will only sell the stuff in a 4x8 sheet for just less than $40.00 a sheet. A bit too rich for me to blow a few holes in, so like Manny, I will go back to the ply.
They usually have 1/4 sheets at HD at the end of the isle or the next one over. Sometimes they have 12" squares of it too. I just happen to have scraps of it laying around, because audio is one of my other hobbies. MDF is the way to go when building speaker enclosures... I'm going to try and do a test in a few days with my small bores. I just gotta find the time and daylight to try it... I also need to get my .177 slug gun sighted in with the new barrel first. I may not even hit the board at the moment,lol!
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I also need to get my .177 slug gun sighted in with the new barrel first. I may not even hit the board at the moment,lol!
Looking forward to seeing what your .177 slug gun does on wooden boards!
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I also need to get my .177 slug gun sighted in with the new barrel first. I may not even hit the board at the moment,lol!
Looking forward to seeing what your .177 slug gun does on wooden boards!
I already know it'll blow right through 3/4 MDF, but it the part after that I'm not sure about ;) Those little .177 slugs penetrate very well, with all the weight behind that tiny diameter. It'll shoot through it at 35-ish fpe, fwiw. I'll do the test with the .177 shooting around 50 fpe, and the .22 around 70 fpe. I just gotta chop up some cardboard and 1/4" ply... I'll try and do it this weekend, if all goes well.
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Post pictures if you can,....looking forward to see results.
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Will do!
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Ik Manny, you have me wanting to test the powerhouses I own, .257 Texan, .458 DAQ, and the .58 DAQ. I know the .458 DAQ will punch a hole through a Dodge Dakota brake rotor, but how far will it go through your test materials? Oh the joy of breaking stuff!
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I found a little MDF scrap in my woodshop today and decided to do a little testing. I think it came from a package something was delivered in and had a few staples in it but I didn't hit them with pellets. It is about 3/8 inch thick and I taped three layers together with painters tape. I will include a couple pictures. My Prod, tuned to about 17 fpe with 14.? grain pellets did not make it through the first layer. A 21.14 grain Barracuda dented the second layer some but was still in the first layer. My guess is it might go through if it was not backed. My 25 Avenger, tuned to about 35fpe with JSB Kings went through with King heavies, almost 34 grains, but not with Kings. It was almost through, however, and I am sure it would go through without the other layers backing. The heavies will go through 3/4 plywood. The Kings do not unless I've already shot that area some. They splinter up the back, however.
How much mdf penetration do we need to reliably go through a pig skull?
I was testing point blank so I would need to test at distance to use the results in hunting. I would also turn the regulator up some, I have it at about 1500 psi - so I could go up quite a bit.
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Cool, thanks for posting with pictures.
Not scientific, but I use 3/4" quality Plywood as my cut off for Big Boars skull penetration, from what I've seen of the MDF probably 3/8" would equal 3/4" Ply ?
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I found a little MDF scrap in my woodshop today and decided to do a little testing. I think it came from a package something was delivered in and had a few staples in it but I didn't hit them with pellets. It is about 3/8 inch thick and I taped three layers together with painters tape. I will include a couple pictures. My Prod, tuned to about 17 fpe with 14.? grain pellets did not make it through the first layer. A 21.14 grain Barracuda dented the second layer some but was still in the first layer. My guess is it might go through if it was not backed. My 25 Avenger, tuned to about 35fpe with JSB Kings went through with King heavies, almost 34 grains, but not with Kings. It was almost through, however, and I am sure it would go through without the other layers backing. The heavies will go through 3/4 plywood. The Kings do not unless I've already shot that area some. They splinter up the back, however.
How much mdf penetration do we need to reliably go through a pig skull?
I was testing point blank so I would need to test at distance to use the results in hunting. I would also turn the regulator up some, I have it at about 1500 psi - so I could go up quite a bit.
I'm not the expert, but I can say you'd want quite a bit more power for the job. At 20 yards, those pellets will have started slowing down a good bit, and even more so at 30 yards. You'll definitely want to do the testing at the yardage you plan to shoot at. I'd think you'd want it to punch through that 3/8 MDF easily at distance. Personally, I want my guns to punch through a piece of 3/4" mdf at distance, just to be sure. This is assuming, the accuracy and shot placement are spot on. I'd rather have more than needed, instead of the bare minimum myself.
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This is what I'm gonna do today :
Going to set up side by side stand alone 3/4" MDF and 3/4" Birch Plywood
I'm going to set up several layers of non packed tight but somewhat loose thin cardboard at about 10-12" distance, that should give me an Idea of the drop after passing through the 2 boards and what kind of penetration difference the pellets will have.
Will be shooting the 34gr JSB out my 65 FPE MAX
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This is what I'm gonna do today :
Going to set up side by side stand alone 3/4" MDF and 3/4" Birch Plywood
I'm going to set up several layers of non packed tight but somewhat loose thin cardboard at about 10-12" distance, that should give me an Idea of the drop after passing through the 2 boards and what kind of penetration difference the pellets will have.
Will be shooting the 34gr JSB out my 65 FPE MAX
This will be interesting!
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Okay, I did a quick and dirty test today. I'm sorry I didn't do as good of a job as Manny did on the documentation :-[ I didn't take a ton of pictures of each layer, and probably forgot to take some pics I should have, because I was short on time. It was starting to rain when I did the shots, I promise I can shoot better, haha. I had planned on doing more shots with different weights, especially in .22, but the weather said no. I basically did a shot, adjusted the HS, did another, etc...
The target was clamped together, but I only had two clamps large enough to grip the thickness. I don't know how that may have affected the consistency of penetration. Given the time constraint, I literally ripped through some pieces of cardboard and ply as fast as I could to roughly match the piece of MDF I had. I did make sure and shoot where I knew all layers were present. The target consisted of:
3/4" MDF
9 layers of cardboard
1/4" plywood
4 layers of cardboard
1/4" plywood
4 layers of cardboard
1/4" plywood
The results pretty much matched the power levels used. I tested the .177 from 45.5 fpe to 54.9 fpe. I tested the .22 at 72.8 fpe and 80.5 fpe :o Obviously, the .22 was the penetration leader, but the .177 wasn't too bad either. Below is the run down of penetration and details.
(1) NSA 20.5 grain .177 slug @ 1000 fps
-Went through 3/4 MDF, and was stuck in 2nd layer of cardboard
(2) Griffin 24 grain .177 slug @ 975 fps
-Went through 3/4 MDF, and was stuck in 4th layer of cardboard
(3) Griffin 24 grain .177 slug @ 1000 fps
-Went through 3/4 MDF, and was stuck in 9th layer of carboard
(4) Griffin 24 grain .177 slug @ 1015 fps
-Went through 3/4 MDF, 9 layers of cardboard, and was stuck in 1rst 1/4 plywood
(5) NSA 31.2 grain .22 slug
-Went through 3/4 MDF, 9 layers of cardboard, 1rst 1/4 plywood, and stuck in 2nd layer of cardboard
(6) Cast 35.2 grain .22 slug
-Went through 3/4 MDF, 9 layers of carboard, 1rst 1/4 plywood, 4 layers cardboard, 2nd layer of 1/4 plywood, and stuck
in 2nd layer of cardboard.
I didn't do the best science here :( It does, at least, give some idea of penetration differences and slug destruction. Note those nice grooves in the .177 slugs from the new Alfa Precision 14.6" twist barrel :D
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Excellent test Rallyshark!
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Cool !!!!
those little bullets look mean :)
I wander if MDF comes in different grades or does it have to be made to certain specks.
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Cool !!!!
those little bullets look mean :)
I wander if MDF comes in different grades or does it have to be made to certain specks.
I could be wrong, but I believe MDF is MDF for the most part. I've never seen different grades of it anywhere. I imagine it's probably called something else, if it is a different grade?
Those little bullets are mean, haha! Interestingly, I got better expansion from the NSA 31.2 grain, when I shot a small pig with it. Just goes to show that soft tissue does really help a hollow point open up. Those little bitty .177s are nasty on the critters too. Here's a picture of one of those 31.2 grain I pulled out of a small pig. He was facing me at an odd angle, so it went into the top of his skull and I found it behind one of his shoulders!
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Excellent test Rallyshark!
Thanks! I would have liked to do a better job with it, but I just didn't have time.
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That goes to show that for mainly penetration purposes a smaller caliber projectile will always function better needing significant less FPE
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MDF = Medium Density Fiberboard. I just read that particle board is low density fiberboard, LDF. I'm not sure I agree with that because the particles are bigger in particle board and it is thus not made of exactly the same material. The top of my router table is a sink cutout made of higher density particle board with laminate glued to it. My impression is the density of that particle board is higher than MDF but I haven't measured it. The same source said tempered hardboard is High Density Fiberboard. That makes more sense to me, it looks pretty much the same except one side is slick, kind of looks finished. Density of MDF was reported to be 35 to 55 lbs per cubic foot. HDF was reported at 50 to 90 lbs per cubic foot. So some overlap even. I already found one questionable thing in their information so I don't know how reliable these densities are. I may look for other sources.
I may make up a different test article out of tempered hardboard. I would use MDF but I don't want a full sheet and haven't seen it in smaller pieces. But I am pretty sure I can get tempered hardboard in 2x4 foot pieces at the local big box stores. Tempered hardboard should be at least as dense as MDF. I want to cut it up into squares and space them at least 1/4 inch apart. It will probably be 1/4 inch thick pieces so I should be able to rapidly see how many 1/4 inch pieces get penetrated. Not sure that going through two 1/4 inch pieces is the same as going through one 1/2 inch piece but it still seems like the information would be interesting.
I'll also look for some smaller pieces of MDF in 1/2 or 3/4 thickness. If I can find it I will buy it and dream up some test. l might also find some scrap to test.
Plywood also has a range of density. It seems likely that the density of the material is the key variable to be able to compare results. Plywood splinters, however, which also probably has some impact. It seems possible to weigh a representative square of the material we use to provide a basis for comparison. Like a foot square piece or something. Or just calculate the density based upon what material you have and what measurement tool you have to weight it (i.e. sensitivity of my reloading scale is a lot different from my fish weight device or the weight scale in my bathroom).
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I just realized I left out the speed on the .22 slugs, although one could work it out with the fpe being given. Anyway, the NSA 31.2 grain were traveling at 1025 fps, and the 35.2 cast slugs were going 1015 fps.
MDF = Medium Density Fiberboard. I just read that particle board is low density fiberboard, LDF. I'm not sure I agree with that because the particles are bigger in particle board and it is thus not made of exactly the same material. The top of my router table is a sink cutout made of higher density particle board with laminate glued to it. My impression is the density of that particle board is higher than MDF but I haven't measured it. The same source said tempered hardboard is High Density Fiberboard. That makes more sense to me, it looks pretty much the same except one side is slick, kind of looks finished. Density of MDF was reported to be 35 to 55 lbs per cubic foot. HDF was reported at 50 to 90 lbs per cubic foot. So some overlap even. I already found one questionable thing in their information so I don't know how reliable these densities are. I may look for other sources.
I may make up a different test article out of tempered hardboard. I would use MDF but I don't want a full sheet and haven't seen it in smaller pieces. But I am pretty sure I can get tempered hardboard in 2x4 foot pieces at the local big box stores. Tempered hardboard should be at least as dense as MDF. I want to cut it up into squares and space them at least 1/4 inch apart. It will probably be 1/4 inch thick pieces so I should be able to rapidly see how many 1/4 inch pieces get penetrated. Not sure that going through two 1/4 inch pieces is the same as going through one 1/2 inch piece but it still seems like the information would be interesting.
I'll also look for some smaller pieces of MDF in 1/2 or 3/4 thickness. If I can find it I will buy it and dream up some test. l might also find some scrap to test.
Plywood also has a range of density. It seems likely that the density of the material is the key variable to be able to compare results. Plywood splinters, however, which also probably has some impact. It seems possible to weigh a representative square of the material we use to provide a basis for comparison. Like a foot square piece or something. Or just calculate the density based upon what material you have and what measurement tool you have to weight it (i.e. sensitivity of my reloading scale is a lot different from my fish weight device or the weight scale in my bathroom).
That kind of goes along with what I was thinking. If it was a different grade of MDF, then it won't be called MDF anymore, haha. I also think 3/8-1/2" MDF would be a better representation of what it would take to poke through a hog skull. That is, assuming the shot is being taken at the right part of the skull. Probably, the only way we could make a more direct comparison with all of out different tests would be to use the same types of wood at a predetermined spacing without the cardboard. Cardboard can be so many different thicknesses and densities of material, and it'd be hard to know that we're all using the same type of that.
Perhaps a good test would be 1/2 MDF front board, with about 5 pieces of 1/4 plywood spaced a quarter inch apart after that. At least, that would be a repeatable test that could be done within the same metrics. Small pieces of 1/4 plywood around the edges could be used to make that 1/4" spacing. I would think we could all match that for good comparisons. I don't have a lot of different guns and power levels to play with myself. Especially since, I'm about to take the .177 off high power and regulate it in the 30 fpe range.
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That is a lot faster on a bigger projectile than my little Prod can handle. 14.3 grain are less than 800 fps with 21 grain going about 700 - so it does not penetrate nearly as well.
I needed to go to Home Depot for something else so I looked at what they had and bought a 1/4 sheet of 1/4 MDF (2x4 feet). I cut half of it into squares roughly 12 inches square and just got done fastening them together with spacers to hold each piece about 3/8 from the others. 3/8 was just the thickness of some little scrap I had. The glue is drying right now but I will shoot them tomorrow or Tuesday. I have 4 layers but I don't expect either of my pcps to go through more than 2 as they are tuned now. But we will see. I have a little data on the penetration of my Prod in wet phone books and in a squirrel so that will be interesting to compare. But I wouldn't be surprised if the first 1/4 inch MDF layer stops at least the lighter Prod pellets.
My Home Depot has quarter sheets of 1/8 tempered hardboard (higher density I believe), 1/2 MDF, and 3/4 MDF. They also have shelving boards of 3/4 MDF that are 4 feet or 8 feet long. I'm sure Hawaii is different but those of us in the continental U. S. should be able to find some material if we want it. The quarter sheet I bought was about $8.
I also weighed one of the squares at 1lb 1 oz. I think that translates to just over 50 lbs/ft3.
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The stage is set :
stand alone side by side 3/4" MDF and Ply
set back 19" several not to tight Carboard sheets
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I definitely agree that 3/8" or 1/2" would be much more representative of a big game skull
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Shots taken
all pass through
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The 2 into the Ply clearly penetrated the cardboards
the 2 into the MDF you can see the slight dent where the bounced off, ...one got riderected quite severely to the right hitting just under the lower hole from the ply one
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The 2 JSB recovered in the ground in front of the cardboard
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The other 2 penetrated several cardboard sheets
one I found in the second to last sheet the other was actually imbedded in the Ply backstop
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The JSB dug out the ply and the other JSB with a good look at how many sheets of cardboard there was
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There's definitely a lot of difference between the ply and MDF it seems. Those pellets basically turned into a gob of lead! Another good test!
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There's definitely a lot of difference between the ply and MDF it seems. Those pellets basically turned into a gob of lead! Another good test!
Yes indeed, 3/4" MDF is significantly more hard to penetrate then 3/4" Plywood,...a lot.
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I just got done shooting my little test article. It is made of 4 layers of 1/4 50lbs/ft3 MDF spaced about 3/8 of an inch apart and glued together. Other than the one .177 shot, all shots were at 20 yards.
The .177 was my little 1377 that is only about 5 fpe. It failed to penetrate a squirrels shoulder so it got retired from squirrel duty. I shot the test article at point blank range and the pellet stopped in the first 1/4 inch layer.
I shot 14.3gr Crosman HP, 14.66 grain H&N FTT, and 21 grain H&N Barracuda into the test article. They all went through the first MDF sheet and stopped in the second. I used my Prod tuned to about 17 fpe with the lighter pellets. I shot a dead squirrel with it using the FTT and Barracuda when it was tuned to about 14 fpe and both stopped in the hide on the off side. I've klled two squirrels with it since raising the power a little and both were not hit in the head initially due either to their movement or my mis-placement. Both did not run off, however. I got another shot into the head of the first and the other one rolled into a rotted area of my kill tree and I didn't have a long enough arm to get him.
I shot the test article with my newer Avenger using FX 25 gr, JSB King Heavies, and H&N Barracudas. The 25 grain pellets are about 35 fpe, the heavier ones closer to 40. All three went through 2 layers, the Heavies were the only one to go into the 3rd layer. The other two left a mark but bounced off. When I shoot over my chinese chronograph I shoot into a couple 3/4 plywood pieces. The heavies are the only ones that go through an undamaged piece of 3/4 plywood.
Difficult to reach too many conclusions from this but my suggestion is that a gun/pellet that will not go through a 1/4 piece of MDF is not suitable for squirrels, probably not rabbits either. We need enough penetration to get to the vitals even with non ideal shot placement. I would further suggest that unless we can get through two pieces with a domed we not use an expanding pellet on small game. Until we can get complete pass through with a domed we will be more humane making a longer if narrower wound channel leaving some margin for shot placement. With pass through of 2 MDF layers, I am pretty sure we will shoot right through a squirrel so using an expanding projectile to make a bigger hole instead of having lead fly through the country side makes sense to me.
Bigger game I think we should stick with domed to get maximum penetration. If we hit bone I would expect the pellet to expand something like it does in MDF. The JSB heavy I recovered looked a bit like a powder burner bullet with an expanded front followed by a bore diameter shank. Others recovered were just flat pieces of lead. Based upon those of you with more experiences comments I think the minimum for a head shot on a hog is probably 1/2 inch of MDF. That seems to be on the order of 40 fpe in 25 caliber with a domed. That is also for a 20 yard shot.
I'm feeling the need to test a bit more before concluding plywood versus MDF but I am leaning towards saying the equivalency is closer than some of you think. 1/2 MDF or perhaps 5/8 MDF = 3/4 plywood. I have not tried multiple types of 3/4 plywood yet, however. I am talking about 50 lbs/cubic foot MDF which I think is the most common.
I'm also hoping one of the squirrels visiting my backyard will slow down enough I can give it lead poisoning and do another penetration test on it. I'd like to know for sure that my current 17 fpe tune is giving me pass through. If so, then through 1/4 inch layer and buried in the second is consistent with pass through.
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Is it me, or does it look like this bullet hit base first?
Okay, I did a quick and dirty test today. I'm sorry I didn't do as good of a job as Manny did on the documentation :-[ I didn't take a ton of pictures of each layer, and probably forgot to take some pics I should have, because I was short on time. It was starting to rain when I did the shots, I promise I can shoot better, haha. I had planned on doing more shots with different weights, especially in .22, but the weather said no. I basically did a shot, adjusted the HS, did another, etc...
The target was clamped together, but I only had two clamps large enough to grip the thickness. I don't know how that may have affected the consistency of penetration. Given the time constraint, I literally ripped through some pieces of cardboard and ply as fast as I could to roughly match the piece of MDF I had. I did make sure and shoot where I knew all layers were present. The target consisted of:
3/4" MDF
9 layers of cardboard
1/4" plywood
4 layers of cardboard
1/4" plywood
4 layers of cardboard
1/4" plywood
The results pretty much matched the power levels used. I tested the .177 from 45.5 fpe to 54.9 fpe. I tested the .22 at 72.8 fpe and 80.5 fpe :o Obviously, the .22 was the penetration leader, but the .177 wasn't too bad either. Below is the run down of penetration and details.
(1) NSA 20.5 grain .177 slug @ 1000 fps
-Went through 3/4 MDF, and was stuck in 2nd layer of cardboard
(2) Griffin 24 grain .177 slug @ 975 fps
-Went through 3/4 MDF, and was stuck in 4th layer of cardboard
(3) Griffin 24 grain .177 slug @ 1000 fps
-Went through 3/4 MDF, and was stuck in 9th layer of carboard
(4) Griffin 24 grain .177 slug @ 1015 fps
-Went through 3/4 MDF, 9 layers of cardboard, and was stuck in 1rst 1/4 plywood
(5) NSA 31.2 grain .22 slug
-Went through 3/4 MDF, 9 layers of cardboard, 1rst 1/4 plywood, and stuck in 2nd layer of cardboard
(6) Cast 35.2 grain .22 slug
-Went through 3/4 MDF, 9 layers of carboard, 1rst 1/4 plywood, 4 layers cardboard, 2nd layer of 1/4 plywood, and stuck
in 2nd layer of cardboard.
I didn't do the best science here :( It does, at least, give some idea of penetration differences and slug destruction. Note those nice grooves in the .177 slugs from the new Alfa Precision 14.6" twist barrel :D
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The bullet is sitting nose down, and may have done a little tumble on the last board it went through. It is also a cup base, so looks are deceiving.
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I got another squirrel this morning (actually two but one was with the car). So I did my penetration test on it's body. At least 3 of the 4 pellets I shot into it at 20 yards went through. So pellets that went through 1 1/4 inch thick MDF piece and into but not through the second went through the squirrel - at least most of the time.
I also know from prior experience that my little 177 that only buried the pellet in the first 1/4 inch piece didn't make it through a squirrel shoulder.
So my opinion is penetration through 1/4 inch of MDF, at the distance you want to hunt, is a good test for small game. If it only goes through and doesn't bury itself in the second you may not be able to go through a squirrel but hopefully it will make it to the vitals.