getting my Cooper M57-M to meet accuracy guarantee

M

millerke01

Guest
I purchased a Jackson Hunter (synthetic version of Jackson Squirrel) rifle last summer and despite trying every type of ammo and technique, I have been able to shoot only one honest 1/4 inch group at 50 yds (with Wolf Target). The test target they sent with the rifle shows (claims?) to be 5 shots in virtually one hole. And they guarantee their rifle should shoot 1/4 inchers with match ammo.

I have tried a lot of ammo types, nothing seems better than Wolf Target so I have settled on that.

Before I complain to Cooper, I am trying to exhaust all other causes, which means something about "me". I can shoot 1/4 inch groups at 100 yds with some regularity with my Remington 22-250, so in theory I think I could shoot 1/4 inch groups at 50 yds with a .22 that was capable. But I must admit that group dispersion is not random, which places suspicion sorely on me. Group variation is generally controlled by vertical dispersion, but sometimes when I change technique I'll get horizontal stringing. Grouping seems unbelievably sensitive to subtle hold and grip variations. I use a wind flag to try and rule out wind affects.

The one 1/4 inch group I did shoot was on a dead calm day, shooting free recoil, adjustable rest on the front with a Sinclair foreend adaptor on the rifle to keep if from rolling over during recoil, owl ear sandbag on the rear. This process only worked once that day, so it was not a panacea.

I think the light weight of the rifle, 6 lbs without scope, is a definite limiting factor. Scope is a 6.5 - 20 Leupold target.

So I have few questions for discussion. Does the light weight and the longer barrel dwell time simply make it quite hard to shoot small groups from a sporter weight .22 LR? Is it simply harder to shoot equivalent MOA groups with a .22 rimfire vs centerfire? What technique would you use at the bench to shrink the groups?
 
Try some Eley Match EPS. One windflag ain't gonna cut it. You won't really be able to shoot free recoil due to the trigger pull and rifle weight. The rifle has to slide very easily back and forth on the bags. This can be tough to arrange with a light rifle. Clean the bbl good before trying the Eley ammo.
 
Everything crb said, especially about the "one" wind flag. You'll need at least 4, 5 is better, I use 7, and don't pull the trigger unless all are showing the same condition.

Just remember when comparing your abilities with a 22-250: a 22-250 is moving a ±55 grn. bullet along @ at close to 4000 f/s while a rimfire is moving a 40 grn. bullet out @ ±1060 f/s = 3/4 the weight @ less than 1/3 the speed! I know it's only half the distance, but do the math, the rimfire is being affected by the wind for longer than the 22-250 as it won't reach its target at 50 Y before the 250 reaches its at 100.

Dave
 
Try cleaning with a patch every 10-15 rounds. Just short stroke the leade or the first couple of inches of the bbl.

I would start from scratch- bronze brush the entire barrel with any good bore cleaner. Then a few dry patches, not squeaky dry. A couple 3 foulers and then fire your group. After 2 groups about 2 or 3 patches short stroked in the leade. Don't clean the entire bbl, let the bbl season but try keep ing the first couple of inches clean.

Wolf Target is very very good in a lot of rifles. Find some SK Standard Plus , about $45 a brick and it shoots excellent. If you get 4 touching and one drops or jumps out a 1/4" or so , thats the ammo. Don't worry about the flyier or dropper, thats not the rifle.

Keep the leade clean first inch of the bbl, until you know how far you can shoot before the leade needs cleaning, all rifles foul the leade at different rates. You might be in for a pleasant surprise!~ Jack C
 
Guys thanks for the advice as I don't have any formal benchrest experience. I'll try the multiple windflags and the leade cleaning. I should have mentioned the 22-250 loads are squib loads with a 40 gr bullet at 2000 fps. Air time is approximately the same as the 22LR at 50.. It is a much heavier gun (stainless steel varmint with fluted barrel) and may just be easier to shoot. Any ideas about shooting techniques to minimize the vertical stringing? I'm pretty sure some of the problem is me.
 
Coopers, at least the centerfire rifles built in the last few years, were test fired at 50 yds or 75 yds (I think), don't know about the rimfires. They will tell you what ammo (or load) that was used in the testing if you call them with the serial #. That may help you some.
 
Another consideration to think about: While the bullets time from muzzle to target may be the same with the 22-250 and 22lr, the 22lr will be in the barrel, and subject to the shooters technique, twice as long as the 22-250.

Sean
 
More ideas: Better ammo...shoot in a tunnel...play with guard screws torque (thats how they "tune" it at the factory) more slip on your bags....proper barrel cleaning....a more solid bench...the list goes on and on. Its cumulative, no one thing except ammo will make a BIG difference but the little things ad up.

If you send it back to the factory they will control the conditions and adjust the screw torque until it shoots one group to their spec and send it back to you. Then you can start chasing your tail all over again to duplicate those controlled conditions. Good luck. bob
 
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