High round count AIAX barrel UPDATE

[bm11]

This is a continuation from this thread: http://www.snipershide.com/shooting...on-guys-who-shoot-lot-barrel-replacement.html

A quick summary for those who didn't follow the original thread: I had some questions about accuracy expectations and when guys replace their barrels. My .308 AIAX barrel has close to 6k rounds on it, most of them hot 155 Scenar handloads, and wasn't shooting like it used to. I was about ready to give up, as I have a fresh AINA .308 barrel ready to go as well as a 550 round AINA .260 Bartlein barrel that shoots lights out for me.

An update from today:

Perhaps this barrel has some life in it after all! I headed to the range today to "put the last rounds through this barrel" before spinning my .260 barrel back on. I was pleasantly surprised by the performance.

I had thoroughly cleaned it before bringing it to the range. The target board was shot at 100, and was shared between a friend (sbaird4000 on here) who was shooting his new MWS with some crappy ammo and with a bit of good ammo, and with me, shooting my AX. The numbered groups are the targets I shot with my AX, and the numbers follow the order they were shot. All measurements are for all 5 rounds, no allowances for "fliers," and represent all 50 rounds I shot (10x 5 round groups.)

Group sizes are as follows:
1: .717" (cold clean bore)
2: .567"
3: .703"
4: .406"
5: .322"
6: .736"
7: .525"
8: .613"
9: .507"
10: .638"

Average group size in inches: .573"
Average group size in MOA: .548 moa

It should be noted that all groups were shot prone, from a bipod, with a rear bag. The average of .548 MOA is an average for ALL 50 ROUNDS SHOT. I didn't non-count any groups, all were calculated in the average. Groups 7 and 8 were with 175 SMK handloads I had loaded to "generic Gold Medal" spec to try in the MWS. They weren't tailored to the AX.

Conclusion? I'm going to keep shooting it. I think I am going to clean more often, as it seemed to shoot well clean and it is getting hard to predict how many rounds are maximum between cleanings to maintain accuracy. I also will continue to keep a close eye on it, as I am "not in love" with this barrel and am willing to replace it when performance dictates. .548 moa for 10 groups of 5 is not bad enough yet.

Thanks for reading,

-Bob

 

[bm11]

As an aside- groups 7&8 were shot with 43.0 grains of Varget over a 175 SMK at 2.810" COAL in FGMM brass with a Federal 210m primer. Both groups would have been in the .2" range excluding one "flier." Perhaps that load is worth exploring further!

 

[Bruiser_Joe]

Keep it up man, push that puppy

 

[NICKNICK]

As an aside- groups 7&8 were shot with 43.0 grains of Varget over a 175 SMK at 2.810" COAL in FGMM brass with a Federal 210m primer. Both groups would have been in the .2" range excluding one "flier." Perhaps that load is worth exploring further!

I know "every rifle is different and what works in my rifle may not work in yours, etc. etc.," but after a fair bit of load development, 42.8gr Varget with 175 SMK at 2.808" is what works for me. It's suspiciously close to FGMM and what seems to work as the "low node" in lots and lots of people's rifles.

 

[TallShot]

Good information. Thanks for the time posting it.

 

[longebow]

bm11:
Have you heard of or tried "final finish" by David Tubb? Might be worth a look (and experiment) to clean up your high round count barrel's throat.
Final Finish & TMS provided by David Tubb
longebow

 

[lte82]

You still may want to take it out to 500+ yards. A worn barrel may shoot well at 100-200 but it can still destabilize at the longer ranges. I will say though that if you are getting 1/2 moa at 100 I highly doubt your barrel is shot out.

Nice shooting by the way.

 

[bm11]

I haven't had the barrel on in the last couple months but haven't tossed it either. It does need to be cleaned more often now, but still shoots better than a lot of brand new rifles an/or barrels.

 

[poison123]

bm11:
Have you heard of or tried "final finish" by David Tubb? Might be worth a look (and experiment) to clean up your high round count barrel's throat.
Final Finish & TMS provided by David Tubb
longebow

....I would never use something like that. A lot of the high round count shooters out there have demonstrated time and again with quality barrels, that as you shoot it out. It'll more than likely lose velocity, and if the accuracy goes you probably just need to seat your bullet longer to account for the growth in headspace.

 

[lte82]

....I would never use something like that. A lot of the high round count shooters out there have demonstrated time and again with quality barrels, that as you shoot it out. It'll more than likely lose velocity, and if the accuracy goes you probably just need to seat your bullet longer to account for the growth in headspace.

I think you mean freebore not headspace.

 

[poison123]

lol ya.....good point.