D54 accuracy expectations

[mcoulter]

I have tremendous gratitude to many folks here who have helped me better understand this rifle, identify its issues (what is normal & what is not), and get it back to good operating shape! 

Most recently, I was able to procure proper fasteners and washers through Héctor and can say confidently that the binding issue with the sled is behind me. 




Also, I have removed the lubrication from the sled mechanism.   Fortunately, the power plant in the gun has been stable and is consistently producing just under 19 fpe with JSB 18.1 and 15.9 grain pellets.  As an aside, I picked up a few tins of H&N Baracuda Match pellets to test in another rifle and out of curiosity threw them in the D54 those heavier pellets are shooting at 15.6 fpe (576 fps).  Oh, I have also tapped back the front sight a bit to better snug down the barrel shroud to prevent it from sliding around.   

I may do some small things like testing how much torque should be applied to the stock now that I have good fasteners both front and rear.  (I have been using 25 inch pounds on both front and rear.)  I will also try to adjust the trigger to eliminate some of the 2nd stage creep I feel in the trigger.  I have largely been happy with the T-06 triggers in their stock form, but I feel with the effort I have put into this gun, I may want to see if it can be improved (I'll be reading up on this, but any suggestions here would be most appreciated.)

So with most of these reasons/excuses behind me, I'm now pondering what consistent accuracy the gun is capable of at 50 yards.  I say consistent accuracy because all throughout my testing I have shot intermittent fantastic groups. 

Here are some recent groups that are pretty representative of how it shoots at 50 yards:






So as I focus less on the hardware of the rifle and more on technique (how and where I hold and rest the gun, how relaxed or tight I am), I wonder what the realistic accuracy for this platform is... 

I had a good stretch of uninterrupted time Sunday afternoon and did quite a bit of shooting.   These were the last series of shots I took on that day and feel like this is the best stretch of shooting that I have had with this gun.  There was a bit of wind that day so I was struggling with some left/right movement in where my groups were hitting, but in large part I felt satisfied with these results.  And I really think that shooting these 12-bullseyes vs. the 5 I typically shoot per target really helped me get into a groove and feel like the gun was listening to what I was telling it to do...




 
I am still playing with a different hold than I have used on any other springer.  I have found that the gun behaves well when I wrap my non-firing hand back under the butt stock and use the rear sling stud as a reference point for one of my fingers.  Holding it this this way seems to create a nice stable cradle for the gun. 

With any luck, I'll be able to duplicate these results again this week.   

Note: older posts about this rifle are here:

Getting to know a 54
https://www.gatewaytoairguns.org/GTA/index.php?topic=172302

D54 pellet testing
https://www.gatewaytoairguns.org/GTA/index.php?topic=173554

[mcoulter]

I always feel weird commenting on my own post, but I wanted jot some things down before I forget them!

1) Be sure to test smoothness of the sled after torquing down the stock.  I found a little too much torque caused what felt like a bump while moving the action along the sled from front to rear.

2) Now that I'm holding the butt end of the stock more deliberately, applying more than a whisker's worth of cheek pressure shifts the point of impact drastically to the right. 

3) As my trigger is currently adjusted, groups seem to benefit from a more deliberate pull.  I am also trying to replicate the "grip fundamentals" described in this article https://www.primalrights.com/library/articles/precision-rifle-marksmanship-grip-technique. 

While this is a pretty messy target, it really illustrates how my d54 will both punish you for bad technique and reward you for better technique.   






And some close ups of the more rewarding groups:

[fwbsport]

Hector sent me targets he shot with mine ending up as a "one holer" at 40 yards.

I can't remember how he fired it but it was in some kind of rest he advocated for others trying to find out what their D54 can do.

[dtdtdtdt]

As mentioned several times, I did an extensive set of tests with my .177 RWS/D54 and my FWB300 for pellet selection..  I shot my groups indoors at 50' because I had access to that range with consistent conditions.  While the results aren't too applicable to your .22 I will put them here. As mentioned several times (I must be getting old and boring!!!) pellet selection is key to good accuracy along with consistent holds.

I use a Caldwell Tack Driver Bag that supports the sides of the stock well enough that one can actually shoot with no other contact.  I didn't do it much but found it interesting.  If I avoided my own tremors etc.  It did OK.  My usual hold system is to have the rifle well supported by the TackDriver bag, cross my arms with the left  below the right.  Trigger pull right-handed with a light hold.  The left hand secures the buttstock carefully with the stock sitting in the web between the fore-finger and thumb positioned near the rear of the stock.  If I need just a little up and down movement of the crosshairs I squeeze or relax my left hand a bit.  I think of it as cuddling the rifle.   It seems to work well for me. Cheek weld is fairly firm - a holdover from powder rifle shooting...

I have the triggers on my air rifles set at about 10-14oz using the light springs that Hector provided me.  I also put a screw through the tab in front of the trigger blade on the T06 to reduce the long first stage pull. 

I notice that if I get a bit sloppy and don't pull exactly front-to-back I can move the POI about 1/4"- 1/2" to the right and up a bit to 2 o'clock with left pressure on the trigger blade.   

I don't shoot outdoors too much as it's quite a drive to the outdoor range and I have serious issues with bright sunny days and my damaged eyes.  I prefer full overcast days with low wind.  Not too common.

Your groups at 50yds are quite good.  The flyers you so are probably wind related or just a bit of side pressure on the trigger. 

I suggest an experiment.  Set up at your 50yd range and shoot repetitively into the same group for 20-30 shots disregarding any wind effects or attempts at Kentucky windage except to avoid shooting in obvious gusts.  When I tried this, I had about 15 shots in about 1-1/4" and a scatter to the right opening up to as much as 3" at 50yds.  Prevailing wind is over my shoulder to about 2 o'clock.  Hence the right bias. 

I did this with my .177 and my .20 Hector Special and got just about the same results except the right bias was a bit less with the .20's heavier pellet.  I haven't tried it with my FWB because its much lower power makes 50 yds problematic. 

[mcoulter]

Thanks for your feedback guys.  I'm very glad that you brought up how I'm resting the gun.  Let's just say that my table leaves room for improvement when it comes to stability.  I'm going back and forth between building a table out of pressure treated lumber vs. something like the Caldwell Stable Table. (https://www.caldwellshooting.com/rests/benches/the-stable-table/252552.html)

The trick is that I need to be able to move whatever I shoot from through the doorway of my shed.  Oh, that tackdriver bag looks nice.  I have been shooting from one of the more simple caldwell bags.  But I lay it down on its side so it's not quite so tall.

Anywho, as I look back at these targets I do feel like I'm "getting there".  At least the variables that are messing me up are slowing being identified and being addressed  :-)

Dave, thanks for your suggestion on the 20-30 shot group.  I'll try that and report back on it.   Oh, I'm sorry to hear about your challenges shooting outdoors.  I'm very glad to hear that you can still make it work inside!

[dtdtdtdt]

I've looked at the Caldwell table too.  My concern was that my wiggly rear-end would affect the movement of the table and make it less stable than most other methods.  Also seems over specialized and expensive.  The standard at ranges is usually concrete blocks and a heavy 2xsomething top. 

I have used everything from an old wooden ironing board to a steel post with a flat top.  The ironing board actually worked pretty well.  It was a junk pile pickup when I was in college.  It was eventually  lost to my mom who needed a better board than she had!!

To set up close to home I use my Workmate with a table top made years ago. Very stable, some height adjustment, folds, and can be transported as needed. You can make a custom shaped top with a clipped corner to make it easy for you to sit near the table and shoot.  I use a wooden stool that I picked off another junk pile (there's a trend here).  The top is 2'x3' made of 2 layers of 3/4" plywood that attaches to the Workmate through a 3' 2x4 running down the middle of the top.  The clamps from the Workmate hold it in place and the plastic clamping stops that Workmate provides keep it stable on the Workmate.  I use it normally as my primary work table in the shop. 

When chipmunking in my backyard, I open the kitchen window and move the breakfast table around.  They never see me coming and the neighbors don't hear a thing except an occasional clank when I check zero on a spinner target that I keep adjacent to the chipmunk kill zone - base of bird feeders.  Chipmunks have caused a lot of damage to the hardscape walls and landscaping (approaching $10,000.). New repairs to be done this summer.  I now am somewhere above 400 kills.  9 in 20 minutes a couple weeks ago. 

[toddbrat]

My wife bought me a portable shooting bench from Rural King a couple of years ago for Christmas. It stays folded up on our screened in deck when not in use. It folds flat and has held up great. You can catch them on sale for about $100 sometimes and isn't too heavy but is rock solid. You can also adjust the seat forward, backward and side to side.

https://www.ruralking.com/deluxe-shooting-bench-12379032

[Fate]

I recently got a Stable Table and it is just that, stable. The rear seat doesn't affect the table and can be moved in a semi-circle to adjust to the angle you need relative to the table. It folds up nice and tight and can be carried in one hand like a suitcase.

It's not brick and 2x6 stable, but shooting from it is stable. It's too big when deployed for my inside space so it's on the rear porch for my outside shooting. It sure beats what I had been using.

My front rest is also a Caldwell, a "The Rock Jr." which is super for me. The supplied bag, over which I have microfiber towels as usual, hold the rifle perfect and yet allows recoil to occur naturally. It's the right height for me and is easily adjustable up and down, and given its cast heavy 3-legged base is a very stable rest. Also much better than my homebrew concoction I'd been using.

Refining my rest and supporting system has enable me to shrink my groups a lot. The most important being the good front rest. For the rear, where I use my fingers to hold the bottom of the stock, I have a small oak block with a rice filled sock on it to stabilize my left hand. The influence of the table is really not a big factor with the gun taken care of now. The Stable Table is more than satisfactory in this case... given I get good groups inside off a relatively wobbly little 2x3 foldable table from wallyworld. The Stable Table in comparison is a brick wall.

[mcoulter]

Jeff, how big is the stable table's footprint when in use?

[dtdtdtdt]

Cheapie version of shooting table.  Not sure why it came out upside down,  No seat belts. 

The magic of computers!  When I clicked on the picture to put in a frame it came out rightsize up.  Who da thunk it1!!


Dave

[truck driver]

Depending on where I'm shooting from I have several options.
I took some scrap counter top and 2X6 and made a  table that slips over the 2X4  deck rail on my deck. Took another piece of counter top and did the same thing but to slip over the window seal of my shed window for when the weather is cold or bad. then there is also a repurposed fold up computer table I had from when the wife wanted to upgrade the computer desk, she got the desk and I got the table. Seating is optional with any of these set ups like what ever you have handy.

[Fate]

Jeff, how big is the stable table's footprint when in use?

Good question Matt, so I just measured it... it's 48" in front measured from the outside of the legs' feet. From the rear of the seat's rear legs it's 52" to the centerline between the front legs. So I guess simply stated, 48" wide by 52" long.

That's simply too long for me where I shoot in the garage, but it makes for a very stable platform in it's natural habitat.

HTH

[Duckfish]

I'm enjoying following this thread.  Like John Wayne once said "You've come a long way pilgrim!"  Just a suggestion, when you take pics of your groups, include an object on the target for size reference. 

[HectorMedina]

Different folks . . .

For ME, and airgun is a field gun. It HAS to shoot well from the hands. And my own personal obsession with FT and other outdoor competitions, take me to like shooting from the sitting position, or with crossed sticks. Have I used benches? yes, but not in the last 30 years, LOL!

I understand we are all different, so do whatever tickles your fancy.

As long as the USE of the gun corresponds with the "testing" or "shooting" setup, you're good.

Keep on shooting!





HM

[dtdtdtdt]

I'm enjoying following this thread.  Like John Wayne once said "You've come a long way pilgrim!"  Just a suggestion, when you take pics of your groups, include an object on the target for size reference.

I agree that he should put some size markings or at least measure the groups for the reader.  With my calibrated eye ball and knowing he has a .22 I can guess approximate group sizes but a lot less strain on my feeble brain......

One group of targets he uses has a note on them that diameter outside of the 4 ring (broad black) is 2.05" +/- 0.1"   That means from the dot in the center to the outside of the black ring is essentially 1".  So most of his groups are around an inch or at worst 1-3/4".

The last batch had notes on them that say the dark ring (10 ring) is .29" while the full diameter of the last ring (8 ring) is 1.7".

[DrPutz]

So reading through all of the treads associated with the 54, is shifting POI usually associated with issues of the sled adjustment?  Attached are my groups from bucket and sticks at 58 yards tonight.  I would get 4 or so shots in one spot then 5 or 6 above or below.  The one next to the dime is 4 shot on POA, then 6 shots about a 0.6 mil high.  Mine is a well used/abused RWS56 that I bought online.  I cleaned the compression tube up, replaced the destroyed seal, straightened the cocking rod and added a vortek kit.  I did not touch the sled and it has a very light adjustment.  It is doing 880 fps with JSB 10.34.  No ZR mount just a UTG MOA mount and 2-piece rings.  If it weren't for the POI shift and the hard cocking, this would be the cat's meow...

Dan

[dtdtdtdt]

At 58 yds off sticks on a bucket, I consider those pretty outstanding groups! 

To do better, I think you would have to start weighing and measuring pellets!  Some years ago, I had a batch of pellets that I did the weighing routine with and found two distinct weight batches in one can.  If I remember right they were about 0.5gr different.  Something like 10.2 and 10.7 gr. families.  I suspect that the manufacturer mixed batches from more than one pellet machine.  Nothing wrong with that but to us picky folks it was annoying. 

A couple shooters that post here a lot buy bulk containers of pellets that are certified as coming from one machine for just this reason.  NCED has discussed doing this and doing a lot of weighing and measuring.  He also shoots bucket & sticks.

A 0.5gr difference would be quite capable of giving vertical stringing at much less than 58 yards.


I consider much of my scatter being my poorly calibrated eyeball and brain connections!!  The only adjustment I made on my sled was to lubricate the back ball a bit and to chamfer the edges of the ball seat just a tiny bit.  I really can't say that it made any difference but it made me feel I was doing something.  When I get group distortion, I can generally attribute it to my less than perfect handling of the trigger pull and accidentally putting some side load on the trigger blade.  Pushing left on the trigger appears to move the POA to the right a bit as the action is moving a bit to the left before the pellet departs and is pivoting around the front end of the action and sled.  Not much but enough to annoy the carp out of me.  I put very light springs in both of mine (12oz trigger pull) and put screws in the T06 trigger to reduce the front stage trigger pull length.  I found the standard pull length nearly a 1cm and shortened it to less than 1mm.  Again, not sure it made much difference in accuracy but it made the rifle easier to shoot for me. 


If you feel your up and down movement is real, may I suggest shooting off a bench to reduce the variables a bit and conciously put up and down pressure on the trigger when firing to see if you can produce the movement that way.

I use targets that have about 70 individual bullseyes and shoot one pellet at each to make the errors very clear.  Something like the one you show.  Zero to dead center the little dot and then shoot each one individually while conciously managing your hold and trigger squeeze.

Cheers and hello!!!



 

[DrPutz]

It seemed to be more than just pellet variability.  It would start off low (or high) then shift the opposite direction.  I would think with variability, I would get random high/lows.  I also head size sort the pellets with the Gaugr.

I did really like the ability to watch the pellet in flight, compared to my other springers.

Dan

[dtdtdtdt]

I have seen pellets in flight too with good light and a strong scope.  The low recoil of the 54 also helps. 

When I said there were two populations of pellet weights, you have to understand how I did the experiment.  I used a gem scale that could reliably detect differences of 0.02 gr versus the 0.2gr (maybe) of the powder scales that most have.  I didn't think they were good enough so bought a more sensitive scale.  (0.001gm versus 0.01gm) I then took a whole tin and separated them into bins of 0.1gr in size.  That is Bin #1 would have 10.0 to 10.1gr, Bin #2 would have 10.11 to 10.19, etc.  '

It was a real PITA to do but I'm stubborn.  At the end, I had pellets ranging from less than 10.0 to over 11gr.  Each bin had some in it.  The bin for the 10.2gr and 10.7gr had much more than the others.  Technically they were probably two Gaussian distributions one centering around 10.2 and the other arougn 10.7.   I didn't do the statistical analysis to test the significance of the difference.
I then shot some from the 10.2 bin and from the 10.7 bin into one group and got vertical stringing.  At the end of the day, I decided that even I'm not that anal so remixed them all and went on with my life.

I don't think any commercial air rifle or powder rifle for that matter, is sufficiently precise to differentiate the small differences seen there.  Olympic-class and custom guns sure!!!  For that matter, I'm the weakest link. 

You might want to try my experiment.  I would love to see the results!  As it is,  your groups are excellent. 

[Fate]

Shooting for accuracy is as much a journey into the self as it is into the gun.