Help Needed with Precision .22LR

[skeeljc]

I am not familiar with that particular rifle, but in my rimfire days I found that the chamber made a huge difference in grouping, the match chamber, being tighter, required a push to engrave the rifling.

The Bergara engraves almost the entire driving band on the bullet. The Bergara extractors will remove an unfired cartridge from the chamber.

 

[turboman]

I shot these three groups back-to-back today. Note the flyer in each group at 12:00. The flyer was always the first shot. I cannot figure what the cause is.

The rifle is a Bergara B14R with a Harrell tuner. The ammo was Lapua Center-X. Distance was 100 yards. The groups were shot from a front rest and a rear bag.

View attachment 1273817

rimfires are picky ya need to foul the bore a few times first before ya shoot for group,i use to shoot ir5050 set a few records as well for a 25 shot target i averaged 75 to 100 shots keeping barrel to temp n reading wind conditions

 

[Carbide]

Well the mystery continues. I shot the Bergara again today, clean barrel (Pro Shot One Step, no brushing).

First target, 50 yards, the number indicated the order shot. Note the "flyers" on the first two targets. Each is 25 fps higher than the other four. Note that the 1st shot flyer is gone by target 9 (72 shots total). I will go back and look at targets 3 through 7 to see if there are any First shot flyers.

View attachment 1277164

Chronograph showed problem. Check bore/ groove dimensions by slugging. May show a bad internal taper. Guess is the groove dimension is in the .223 range and barrel will never be consistent unless under rapid fire rate. Standard is .222-.217. Most good match barrels are .221-.2215 groove. A lot of European bore- groove barrels are tighter >.220-.215. Short barrel is not helping matters. Eley told Anschutz years ago not to do barrels under 19" or what ever the MM designation was.

 

[coldboreshot]

I too have experienced this with my .22 rimfires. This is how it was explained to me by a long-time bencher and rimfire competitor;
For their matches, the targets were laid out with a separate aiming section for first shots and/or sighters. This is designed to bring the barrel to temp after that initial cold bore. Once the relay of their set number of shots for record was over and a period of downtime existed, the process would begin all over again. It may be different degrees of duration between sets with the type of barrel material and ammo used but it seemed to be very consistent. I have experienced this exact thing. I've tried the first shot then 10, the first shot then 15 and the first shot then 20...and in every case, that first cold shot flew and all after that settled in.. If anyone out there can corroborate this, please advise.
I'd like to know if I was provided the proper explanation or not, but to me, kinda makes some sense.

 

[Thauglor]

I too have experienced this with my .22 rimfires. This is how it was explained to me by a long-time bencher and rimfire competitor;
For their matches, the targets were laid out with a separate aiming section for first shots and/or sighters. This is designed to bring the barrel to temp after that initial cold bore. Once the relay of their set number of shots for record was over and a period of downtime existed, the process would begin all over again. It may be different degrees of duration between sets with the type of barrel material and ammo used but it seemed to be very consistent. I have experienced this exact thing. I've tried the first shot then 10, the first shot then 15 and the first shot then 20...and in every case, that first cold shot flew and all after that settled in.. If anyone out there can corroborate this, please advise.
I'd like to know if I was provided the proper explanation or not, but to me, kinda makes some sense.

That doesn't explain anything, that is a procedure to deal with a cold bore first shot problem

 

[coldboreshot]

That doesn't explain anything, that is a procedure to deal with a cold bore first shot problem

I think the idea revolves around the initial barrel warm up from the first shot. I've tried it. When the barrel cools back down, the next shot is off and the rest settle. If there was anything to do with fasteners, scopes, barrels touching stocks, etc...more than just the first shot would be effected considering the strings I would test were 10,15 and 20 shot sets with time in between each.

 

[jlmurphy]

Airgun match barrels were designed with a choke at the muzzle, made a big difference in eliminating fliers, rimfire is similar. There was a writer/smith for Precision Shooting years ago that was REALLY into rimfire, he would slug the barrel and would cut it at the tightest spot, regardless of length. I see the subject rifle has a tuner, if it was threaded, the bore may have expanded, counter boring the muzzle might fix it. In any case slugging the bore would be revealing.

 

[Thauglor]

I think the idea revolves around the initial barrel warm up from the first shot. I've tried it. When the barrel cools back down, the next shot is off and the rest settle. If there was anything to do with fasteners, scopes, barrels touching stocks, etc...more than just the first shot would be effected considering the strings I would test were 10,15 and 20 shot sets with time in between each.

Yes. We all know that, but not what is causing it. Even the OP shows that after the first shot it settles down

 

[dave@aDave]

Airgun match barrels were designed with a choke at the muzzle, made a big difference in eliminating fliers, rimfire is similar. There was a writer/smith for Precision Shooting years ago that was REALLY into rimfire, he would slug the barrel and would cut it at the tightest spot, regardless of length. I see the subject rifle has a tuner, if it was threaded, the bore may have expanded, counter boring the muzzle might fix it. In any case slugging the bore would be revealing.

Bill Calfee.

 

[Old Tanker]

The first round in the mag might be under a little more tension and maybe sitting more level. As the bolt closes, the extra tension and angle may be causing some wax to be shaved on one side of the bullet. Try loading four in the mag and manually loading your first round. Also try a ten round mag and shoot two groups. If no flier in the second group, you know something is happening to the first round as it enters the chamber.

 

[skeeljc]

I shot this group with the Bergara B14R today when the wind settled down. I don't recall if the shot not touching the others was the first shot or not. I did shoot other groups with no "flyers". I am going to chalk the earlier "flyers" up to the rifle not being settled into the bags.

 

[Hunting 2019]

That's a good group at 100 for sk std plus. I would buy all of that lot I could get my hands on!!

 

[skeeljc]

I only bought 2 bricks off of Gunbroker (ukrbond)

 

[skeeljc]

I shot the Bergara again today. I hung a strip of ribbon next to the target at 100 yards and only shot when the wind laid down. These groups were shot from a front rest and a rear bag. Order was left to right, top row, then bottom row.

 

[drover]

You need to get out a couple of wind flags between you and the target. The wind at the target has the least effect on the bullet. Set out a flag at 35 and 75 yds, they will give you a more realistic idea of what is happening between you and the target.
Don't be surprised if at times you see all three flags pointing different directions.

 

[seymour fish]

I shot the Bergara again today. I hung a strip of ribbon next to the target at 100 yards and only shot when the wind laid down. These groups were shot from a front rest and a rear bag. Order was left to right, top row, then bottom row.

View attachment 1279972

Points to consider: 1) first round out of a full mag shaving the bullet -single feed to rule it out 2) cold bore flyer - with increased velocity - this is condensation in the barrel until proven otherwise. 3) if a mere 20 FPS delta throws a flier, the gun is way off tune 4) shooting in “no wind” can be tricky. One flag won’t work. Better to shoot in a steady breeze. 5) you have a tuner. Your last targets are out of tune. 6) hold onto the gun and see what happens. 7) let some lead ring build up at the throat. Monitor it with a bore scope. See what that tells you. 8) conversely, keep just the throat clean to bare metal and count number of shots to come in, and number of useful shots before goes south. Borescope along the way. See the pattern. 9) some of this may apply, or not. Good luck with your quest. Seymour

 

[skeeljc]

Points to consider: 1) first round out of a full mag shaving the bullet -single feed to rule it out 2) cold bore flyer - with increased velocity - this is condensation in the barrel until proven otherwise. 3) if a mere 20 FPS delta throws a flier, the gun is way off tune 4) shooting in “no wind” can be tricky. One flag won’t work. Better to shoot in a steady breeze. 5) you have a tuner. Your last targets are out of tune. 6) hold onto the gun and see what happens. 7) let some lead ring build up at the throat. Monitor it with a bore scope. See what that tells you. 8) conversely, keep just the throat clean to bare metal and count number of shots to come in, and number of useful shots before goes south. Borescope along the way. See the pattern. 9) some of this may apply, or not. Good luck with your quest. Seymour

All of the targets were shot without the tuner. I do have my head resting on the comb but the butt is not on my shoulder. The far out first shot flyers I had in the beginning og this thread appear to be gone. All the recent rounds were from the magazine. The Bergars cycles rounds from the magazine really well. Very smooth and no binding as the round is chambered. I wish my CZ457 would cycle like the Bergara from the magazine.