Rapidly expanding groups?

[4xforfun]

Sounds like it needs a little more break in, I would repeat the brake in process and see if it improves. (Some barrels need more brake in than others).

It is not unusual for this to happen after 6 or 7 shots until it is broke in well.


J E CUSTOM

Well, there is no way posable to count the number of guns that I have both shot and did load work up on...and I have NEVER seen this. So, yes, it IS unusual.

 

[J E Custom]

Well, there is no way posable to count the number of guns that I have both shot and did load work up on...and I have NEVER seen this. So, yes, it IS unusual.

Your experiences must be different than Mine because I have built many rifles and worked on many factory rifles and have been reloading for over 50 years and can almost predict how many rounds it will take before it becomes fouled based on the bore scope inspection of the barrel and the amount of machine/tooling marks.

Many Premium barrels break in within 7 to 10 rounds and clean up with one or two solvent patches and a light brushing. I have seen factory barrels that needed 50 or 60 and some never really cleaned up and had machine marks for the rest of there life.

If you start with a totally clean barrel and shoot groups, It will tell you when fouling has effected the accuracy. After fouling some barrel will shoot well for many rounds, just not as good as when the barrel is not fouled. Most will find that when shooting a 5 shot group, the lase shot is never as good as the first 2 or 3 and the group opens up a little.

Depending on the condition of the bore the number of good shots can range from 3 to over 10. Some like to shoot 10 shot groups to see when accuracy is effected and to get realistic groups and SDs.

On really accurate rifles (Those that shoot less than 1/10th MOA) this really shows up as a distinctive change in accuracy and can double the group size.

Just My experience.

J E CUSTOM

 

[Canhunter35]

On my R.E.M. Milspec it tightened up a lot somewhere between 400-500 rounds, but shot sub Moa the whole time, now it's .35-.45 Moa when I have a good day

 

[J E Custom]

On my R.E.M. Milspec it tightened up a lot somewhere between 400-500 rounds, but shot sub Moa the whole time, now it's .35-.45 Moa when I have a good day

Sounds like this was one of those rifles that took a long time to get broke in. If you don't clean often (Remove fouling) the fouling can slow the break-in process.

It may even get better over time.

J E CUSTOM

 

[vividus1]

Are you shooting it after cleaning on a completely dry barrel?

I run a very very light oil patch through it after clearing the copper...I've been told that the copper solvent will strip all oil out and that is not a good thing either. Agreed?

 

[vividus1]

Thanks again for all the replies...helps a newb like me for sure. So I scrubbed the bore totally clean with J-B (like 50 strokes with a bore brush with a couple applications of J-B, which a Browning tech told me to do), ran a couple of patches Hoppes bore cleaner afterward to ensure J-B was all out, then a very very light oil patch. Went out and shot only the Barnes LRX with no cleaning of any kind between shots/groups...the rifle behaved like I'd expect which is to say it shot well. I shot two 10 shot groups (one at 100 yards, one at 200) allowing time between shots for the barrel to cool to ambient conditions; the 100 yards group was right at 1.25" including a minor "flyer"...the rest all touched. The 200 yard group stayed just under 2" and now I'm a fairly happy camper. The rifle now has about 70 rounds and the follow-up clean was much easier than any of my previous bore cleans.

Browning tech told me a few things could be in play 1) could easily have a minor barrel inclusion that needed more time to shoot out and was thus copper fouling badly in one spot. 2) mix and matching the Accubonds and LRX (or often any other monolithic and bonded bullets) without removing the copper between them causes all sorts of unpredictable bullet flight due to the differences in copper alloys. 3) that the velocity this gun demonstrated on the chronograph can make this and any other fast gun touchy in general in regards to cleaning. He also told me to take care to clean the throat carbon out after about 50-100 shots. I hope some of this info may help somebody else sometime!

 

[Georgiashooter]

Just caught this thread and was about to suggest sticking with one bullet as when I've mixed different makers bullets results were unpredictable as you've experienced. JE is right on as well. Glad you got it worked out. Happy shooting

 

[4xforfun]

Your experiences must be different than Mine because I have built many rifles and worked on many factory rifles and have been reloading for over 50 years and can almost predict how many rounds it will take before it becomes fouled based on the bore scope inspection of the barrel and the amount of machine/tooling marks.

Many Premium barrels break in within 7 to 10 rounds and clean up with one or two solvent patches and a light brushing. I have seen factory barrels that needed 50 or 60 and some never really cleaned up and had machine marks for the rest of there life.

If you start with a totally clean barrel and shoot groups, It will tell you when fouling has effected the accuracy. After fouling some barrel will shoot well for many rounds, just not as good as when the barrel is not fouled. Most will find that when shooting a 5 shot group, the lase shot is never as good as the first 2 or 3 and the group opens up a little.

Depending on the condition of the bore the number of good shots can range from 3 to over 10. Some like to shoot 10 shot groups to see when accuracy is effected and to get realistic groups and SDs.

On really accurate rifles (Those that shoot less than 1/10th MOA) this really shows up as a distinctive change in accuracy and can double the group size.

Just My experience.

J E CUSTOM

..and your groups open up to 6 - 8 inches?? 6 - 8 inches is a regular occurrence with the guns you build?

 

[J E Custom]

..and your groups open up to 6 - 8 inches?? 6 - 8 inches is a regular occurrence with the guns you build?

I don't know what you are trying to say, but all of the rifles I build start out below 1/2 moa and only improve with Break in and only get better with time and loading.

A rifle that wont shoot less than 1 MOA at any distance is not acceptable for any use especially for long range shooting/hunting.

Even the worst barrel wont shoot worse than 1.5 MOA if everything else is correct. The barrel is the heart of accuracy, everything else is secondary except the shooter.

A good shooter cant make a bad barrel shoot well. Just like a poor shooter cant expect accuracy just because he has a great barrel.

Also just like poor Gunsmithing, A poorly machined barrel bore can only produce mediocre results. Copper fouling acts just like poorly machined barrel bores, It is uneven and inconsistent and produces the same basic results, Inaccuracy.

I don't have to defend the accuracy of my rifles because they speak for themselves. (Just ask anyone that owns one).

J E CUSTOM

 

[4xforfun]

I don't know what you are trying to say, but all of the rifles I build start out below 1/2 moa and only improve with Break in and only get better with time and loading.

A rifle that wont shoot less than 1 MOA at any distance is not acceptable for any use especially for long range shooting/hunting.

Even the worst barrel wont shoot worse than 1.5 MOA if everything else is correct. The barrel is the heart of accuracy, everything else is secondary except the shooter.

A good shooter cant make a bad barrel shoot well. Just like a poor shooter cant expect accuracy just because he has a great barrel.

Also just like poor Gunsmithing, A poorly machined barrel bore can only produce mediocre results. Copper fouling acts just like poorly machined barrel bores, It is uneven and inconsistent and produces the same basic results, Inaccuracy.

I don't have to defend the accuracy of my rifles because they speak for themselves. (Just ask anyone that owns one).

J E CUSTOM

I 100 % believe you and the quality of your work. You reputation is top notch and well known on this sight. In the OP, the poster says that within 6 to 8 shots the groups open up to 6 - 8 inches. You said that this was common!! You then used your experience as a rifle builder to explain. We are talking 6-8 MOA groups here. I'll bet money that you have NEVER seen a rifle go from 1/2 to 3/4 MOA groups to 6 - 8 MOA groups in 6 shots because it wasn't broken in enough. Maybe because something else is FUBAR or otherwise broken, but not because of fouling due to break in. And, if it was possible, I'd say NOT with a custom tube!! Your statement that a poorly machined bore can only produce mediocore results....1/2 to 3/4 MOA is not Mediocre. The thing shoots good , and then it does not shoot at all...and it is repeatable.

Tod

 

[J E Custom]

I 100 % believe you and the quality of your work. You reputation is top notch and well known on this sight. In the OP, the poster says that within 6 to 8 shots the groups open up to 6 - 8 inches. You said that this was common!! You then used your experience as a rifle builder to explain. We are talking 6-8 MOA groups here. I'll bet money that you have NEVER seen a rifle go from 1/2 to 3/4 MOA groups to 6 - 8 MOA groups in 6 shots because it wasn't broken in enough. Maybe because something else is FUBAR or otherwise broken, but not because of fouling due to break in. And, if it was possible, I'd say NOT with a custom tube!! Your statement that a poorly machined bore can only produce mediocore results....1/2 to 3/4 MOA is not Mediocre. The thing shoots good , and then it does not shoot at all...and it is repeatable.

Tod

Sorry Tod
I missed the part about 6 to 8 MOA groups. I have never seen a rifle shoot that Bad, probably because the second it started to shoot like that, I would stop shooting and try to figure out what was wrong. I will also re visit the post and see what else I missed.

Many things can cause a rifle to shoot badly (Not that badly though) and if you start to eliminate things you can probably figure it out.
Some of the best groups I have fired have been while breaking the barrel In because it is cleaned every shot and the shots are fired in the same conditions.

There are many reasons for accuracy to fall off, and fouling is only one of them. There is a long list of things that can ruin the accuracy and that could be another post all by it's self.

Again: sorry
J E CUSTOM

 

[Jeremy338]

I've had good luck with kg products. Kg2 on a clean bore works miracles. Kg 1 then kg 12. Hit it with kg 2. Good to go

 

[LongBomber]

The 26 is a very overbore and finicky gun to load for, after owning two I can see it putting out some huge groups with a bore issue. Both rifles were pretty touchy as to exactly what they liked. The best loads in my fierce run 1/4-1/3moa, but loads it doesnt like are spray and pray- sometimes 2-3 moa easily. So I can see a bore that is picking up copper throwing shots, 6-7moa is out there, but then the 26 is pushing things as well.

 

[Canhunter35]

Sounds like this was one of those rifles that took a long time to get broke in. If you don't clean often (Remove fouling) the fouling can slow the break-in process.

It may even get better over time.

J E CUSTOM

I actually considered it broke in then it seemed to get better and better. I always thought it's just a factory barrel smoothing out over time. Hopefully it does keep improving!