GTA
All Springer/NP/PCP Air Gun Discussion General => European/Asian Air Gun Gates => German AirGun Gate => Topic started by: ibgp3 on December 09, 2013, 06:18:07 PM
-
I bought several 300S's from an ROTC unit. One of them was "broken".
"Broken" appears to be a steel BB caught in the choke and at least 6 inches of epoxy behind it.
(I'll bet there was a story there!!)
As I thought about ways to deal with the blocked barrel, (other than the trash can), I remembered having a powder burner drilled out from .22 to 6.5mm.
Is it normal, unusual, unheard-of for one of these fine old AG's to be drilled out?
There appears to be plenty of metal for .22 or even .25
Is it reasonable to expect a springer that pushes a .177 7.4gr pellet out @ 650fps
to push a .22 14gr pellet@ 475fps?
or a .25 24gr pellet @ 360fps?
Even if the accuracy was still there, would the slower .22 or .25 be adequate for even rats?
Is there a way to tune it to push the velocity to a useable level?
My experience is with powder burners, so I need good advice.
I see three choices:
1. Rebore
2. part out the rest
3. find a barrel
other choices?
reccomendations?
-
If you drill it out, there would be NO rifling. I'd opt for #3. Find a barrel for it, or option #2 and part out the rest of it.
Bill in SC
-
I don't know if it would work, but you may be able to heat it to soften the epoxy a bit and then push it out with a brass rod. I know it's not exactly on the "approved list", but neither is putting epoxy into a barrel. What were they thinking?
-
I don't know if it would work, but you may be able to heat it to soften the epoxy a bit and then push it out with a brass rod. I know it's not exactly on the "approved list", but neither is putting epoxy into a barrel. What were they thinking?
Excellent idea to heat the barrel to remove the epoxy! As to what they were thinking to begin with, I would guess that they wanted to render gun to be inoperable, like the military plugs barrels on surplus artillery pieces. NO idea WHY they would want the gun inoperable, but they did a good job of it.
Bill in SC
-
Sounds like the "plug" is at the front.
Another option is to cut the barrel short of the plug.
But if they poured epoxy from the breech down the barrel, then the entire length of the unplugged barrel is suspect.
I don't know if the barrel of the 300 was choked or not. It it was, you loose the choke when you cut the barrel.
Also depending on the specific model, if you cut the end of the barrel, you loose the ability to install a front sight on it. Cuz the machining for the front sight is pretty precise. Well you could drill and tap the front sight and use a set screw to secure the front sight. However, it would not be as secure as the tapered pin.
You might be able to get a bit more velocity out of the gun with a spring swap.
But pushing a LOT more velocity will not work. When it fires, the sledge will impact the end of the rail, and you have recoil, and possible damage. The cocking and trigger mechanism may not stand up to a much stronger spring.
If you want to shoot it, then I would try to replace the barrel.
If you don't really care to shoot it, then part out the rifle. If the rifle has a nice walnut stock, I am pretty sure a bunch of guys would like to replace their beech stock with a walnut stock.
-
Yup ... screw with un-screwing the barrel to the point of screwing up the barrel ;D ;D ;D What ya got to loose ?
Heat indeed will soften the epoxy, expand bore size slightly allowing "Hopefully" to be able in driving out all the C*ap lodged in there out from the muzzle end. 200-250*f is not out of the question here ;)
Once cleared ... re-post and we'll do our best walking you threw the bore clean and polish likely required once your at that juncture ;)
-
Roadworthy: There is no sealing ring on the compression cylinder, and there is no buffer on the piston. My guess is that parts were not available for some reason and someone thought they would make their own.
...then, oops, that didn't work!!
There appears to be epoxy in the air line in the compression cylinder, but I am assuming that it is a straight line passage and can be drilled out. I'll take one of the others down and verify that.
Bill: My powder burner rebore job (.22 to 6.5mm) got new cut rifling and actually had better accuracy than before.
The 300S is great, in my mind for three reasons:
1. superb accuracy
2. k illing power
3. mechanical endurance.
Motorhead is right, I lose nothing but time screwing with the barrel, but would I ever expect to get it back to factory accuracy? I wouldn't want to keep it and who would want to buy it?
I've seen videos that claim to show a 300S pushing a pellet all the way through a tin can full of water at 100yds; and pictures of 100 yd quarter sized groups. Put those two together and I could feed my family with one....but I have three good ones, if I get one to factory for me and sell the other two, I'm done.
I know that a rebore would work, but if I no longer have k illing power
or
if I over-stress the mechanism and lose the mechanical endurance
Then I would have less than a factory rifle after spending some serious coin.
It might be a one of a kind, but I already have a few of those.
Is there a good place to buy a barrel and receiver, or sell the other parts?
AC12: The Stock is incredibly light and has very little figure. I assume beech. I had originally planned to adapt a plastic stock for mine, but this is so light I will skeletonize it some and add a truck-bed finish.
Thanks for the input.
I think I am down to either
2. part out the rest
3. find a barrel
-
Scott called it, what you got to lose?
I vaguely recall seeing something about barrel liners out there somewhere, although I'm not at all familiar with them. So if you did bore out the barrel, might look into that instead of trying to re-rifle it. Would be cheaper to get a new barrel. That would be my preference, if everything else checked out ok.
It should have a steel piston ring, kinda like in a car engine. And a bumper to keep the piston from crashing into the end of the cylinder.
I shot my first FT match with a 300, kind of like lobbing morter shells at the targets. At 50 yards, you shoot and then have time to count to 10, waiting for the pellet to 'ting' off the faceplate. I did manage to knock a few down even so, and scored into double digits. Accuracy counts too, in addition to power.
-
put some heat on it ;D it'll clean up ;D those rifles have Anschutz barrels in them IIRCC the their pretty hard :o theirs no need to drill anything and same for the compression tube! after you heat it up use a good solvent to remove the rest of the epoxy JMO :P
-
I think heat application is a good idea.
Face it, the gun is older, and maybe the bluing is not so good anymore. FWB were never famous for bluing quality. Put heat on it, easy and over a greater area if possible to reduce warping.
Maybe try a long thin bit and a precision drilling device to loosen up, and also to check exactly what is in there.
Interesting project you have going.
-
wait till momma will be gone for a while,
...put the barrel-receiver in the oven @ 175 for an hour
then @ 200 for an hour
then @ 225 for an hour
then @ 250 for an hour
then let it cool, or work it hot?
-
HOT.
The junk when it cools may only get tougher!!!!
I'd say when very warm!!!, you still need gloves....go in there with some prodding piece to get most of the sticky stuff out.
Should you see that the substance is white and powdery, your home free! Even cooled down, these types of epoxy will separate easily and can be removed with little force.
You may however, need to reapply the heat to reduce the rest.
-
Yep ... Protect your self from getting burned ... but work it HOT !!!
-
time for two ove-gloves
-
300S is a 10 meter target rifle, not a varmint gun,'ceptin' flies. Shoot completely through a water filled tin can at a hundred yards? I've got a bridge in Brooklyn for ya. Shoot, a Diana 350 can't do it! Rebarrel or part out. Sounds like a much abused gun to start with.
-
Like the State Farm commercial
"They can't put anything on the internet if it isn't true."
If it does not make sense, it is suspect as a fraud.
And as RedFeather said, a 300 is NOT a 100 yard can busting rifle. My guess is that video you saw was rigged.