View Full Version : New Upper not grouping
I recently put together a new upper that simply will not group. 5 shot groups will typically print around 6-8 MOA at 100y. With my other upper using the same ammo and optic I typically see somerhing like 2-2,5MOA at the same distance.
The not so great upper consists of:
Rainier Arms Billet Upper receiver
Faxxon 16” middy barrel cut to 12,5” by a gunsmith. (1/7 twist)
IMI BCG
Schmeisser adjustable fas block
BCM KMR10
Things I’ve tried so far without any change in results
- Cleaning barrel with copper solvent
- Testing 3 different optics (both magnified and non-magnified)
- Testing with 62gr M855 and 55gr American Eagle FMJ.
- Testing different BCG
- Checked crown on barrel. No burrs, marks etc. Testfired both with and without the flash hider
- Disassembled complete upper, cleaned, checked everything (nothing was loose) then reassembled as per instruction. From what I can see nothing inside the handguard (gas block etc) touches the handguard.
I feel like I’m getting to the end of the road here. Any auggesstions? Anything obvious that I missed or should check?
Likely the barrel. Pappabear had a faxon that we shot a few hundred rounds trying to get it to group. Eventually sent it in, and Faxon said it looked like it had 10k through the bore. Did nothing to make their junky product right.
- Testing with 62gr M855 and 55gr American Eagle FMJ.
Neither of those are match grade bullets but you somehow expect match grade accuracy?
Especially the M855 crap... If you get better than 'minute of milkjug' with that you did well.
Neither of those are match grade bullets but you somehow expect match grade accuracy?
Especially the M855 crap... If you get better than 'minute of milkjug' with that you did well.
You really consider 2-2,5 MOA match grade precision?
M855 or european NATO equivalents have shot 2-3 MOA in all my rifles. AR, FNC, Bolt guns…
You really consider 2-2,5 MOA match grade precision?
M855 or european NATO equivalents have shot 2-3 MOA in all my rifles. AR, FNC, Bolt guns…
I have to agree here. M855 could produce 2-3 MOA groups out of a match grade barrel. Sure the same barrel may print a 0.75MOA group with Mk262 but 2-3 from M855 isn’t unreasonable.
I wonder if the smith effed up the barrel when he cut it down?
You really consider 2-2,5 MOA match grade precision?
M855 or european NATO equivalents have shot 2-3 MOA in all my rifles. AR, FNC, Bolt guns…
Solid assessment. If you have any SMK’s, run a few groups through just to be sure.
I also don’t want to insult you’re intelligence, but maybe assembly wasn’t the greatest. Have another builder look it over? And yeah, faxin’s have been known to suck.
From my pretty amateur gunsmith standpoint hard to tell. Barrel crown looks good at least. But since barrel sits solid in the upper and the rifle works fine in all other aspecs you obviously habe to suspect the barrel. Shame on a pretty much new barrel…
The Faxon is generally not a great quality barrel, and commercial M855 and 55-grain American Eagle are average to below-average (at best).
Seeing as you're in Sweden, have you tried one of the local commercial ball or match ammunition options? Perhaps Nammo or Lapua, or maybe an import like IMI, MEN, or Fiocchi?
The Faxon is generally not a great quality barrel, and commercial M855 and 55-grain American Eagle are average to below-average (at best).
Seeing as you're in Sweden, have you tried one of the local commercial ball or match ammunition options? Perhaps Nammo or Lapua, or maybe an import like IMI, MEN, or Fiocchi?
To be honest: I have not. M855 is my main squeeze so having the rifle shoot at least ok with it is a deal breaker unfortunately. On top of the the ammo shortage is a thing vere aswell I’m afraid.
I have tried different M855 (both Lake City and our local variant the the swedish army uses) with the same result. Seing as they’re produced to basically the same NATO-spec that shouldn’t be a surprise on the other hand.
Maybe trying another barrel is the best option atm.
I have to agree here. M855 could produce 2-3 MOA groups out of a match grade barrel. Sure the same barrel may print a 0.75MOA group with Mk262 but 2-3 from M855 isn’t unreasonable.
I wonder if the smith effed up the barrel when he cut it down?
OP not using a 'match grade' barrel here.
Even if he was, and even if he went to great lengths to 'tune' those things to his particular rifle - They are only going to do the best they can. (which is not great)
While I wouldn't expect M855 and American Eagle ammo to deliver 2 MOA, the result of 6 to 8 MOA is on a whole other level of shitty.
Even if SMKs deliver .5 MOA, what does it matter? The OP doesn't plan to put SMKs through this barrel. It's not like he can call Faxon and get them to do anything about a barrel that was cut down.
There are lots of good 11.5 to 12.5" barrels that should be capable of the 2-3 MOA with mediocre ammo that the OP requires.
While I wouldn't expect M855 and American Eagle ammo to deliver 2 MOA, the result of 6 to 8 MOA is on a whole other level of shitty.
Even if SMKs deliver .5 MOA, what does it matter? The OP doesn't plan to put SMKs through this barrel. It's not like he can call Faxon and get them to do anything about a barrel that was cut down.
There are lots of good 11.5 to 12.5" barrels that should be capable of the 2-3 MOA with mediocre ammo that the OP requires.
Curious if you (or anyone else claiming 2 to 3 MOA is 'easy' with these rounds) have ever looked up the accuracy spec for M855?
FWIW - I wasted a lot of time and effort one time handloading SS109 pills (new / not pulled IMI brand) and shooting them out of a good 'match grade' barrel of mine in an attempt to see if I could make them perform better than the factory M855 did (on average) out of factory Colt barrels.
Think SS, Bull, Match chamber, Cryo Treated, etc. vs several different rack grade Colt rifles chambered in 5.56.
https://i.imgur.com/WVBhnLR.jpg
Now think of stuff like weight sorting the bullets (which are all over the feakin map in weight), trying multiple different types of powders and charge weights, carefully selected and processed brass...
Old picture but guessing you can get the idea here:
https://i.imgur.com/8JBKRz2.jpg
The unmarked bins on the right (that kept filling up fast) were the bins for the ones that were WAY off from what they should have been. 2 grains + 'off' IIRC. Filled a small bucket with those bastards.
In the end - Was a waste of time, good powders and of barrel life sending that garbage downrange and expecting anything other than mediocre accuracy in my testing / experiments. :sad:
Had a similar experience shooting all sorts of different Russian ammo out of an otherwise perfectly good Colt 7.62 x 39 upper I had. Minute of Milkjug at BEST. Started feeding that upper good / fair quality, brass cased, American mfg ammo and noticed a night and day difference right away.
Every time I think about SS109s and trying to load them for accuracy I think about the saying - 'the juice not being worth the squeeze'. Makes no difference if you have a bad ass expensive juicer from hell AND went to a special juicing school so you could learn how to juice like the 'pros' if you are working with a pile of rotten oranges. You will end up with crappy juice no matter what.
To be honest: I have not. M855 is my main squeeze so having the rifle shoot at least ok with it is a deal breaker unfortunately. On top of the the ammo shortage is a thing vere aswell I’m afraid.
I have tried different M855 (both Lake City and our local variant the the swedish army uses) with the same result. Seing as they’re produced to basically the same NATO-spec that shouldn’t be a surprise on the other hand.
Maybe trying another barrel is the best option atm.
Honestly, I would try a couple boxes of commercial sp/hp/tipped .223. They generally shoot better than FMJ ammo and may provide a clue to what the barrel can do.
While I would not recommend a Faxon barrel knowing the problems others have had, the one I owned shot very well.
Andy
Curious if you (or anyone else claiming 2 to 3 MOA is 'easy' with these rounds) have ever looked up the accuracy spec for M855?
FWIW - I wasted a lot of time and effort one time handloading SS109 pills (new / not pulled IMI brand) and shooting them out of a good 'match grade' barrel of mine in an attempt to see if I could make them perform better than the factory M855 did (on average) out of factory Colt barrels.
Just to make sure: M855 is the standard 62gr SS109 right?
I actually visited the Nammo plant (the big ammo producer here in Sweden www.nammo.com) a few years ago. I asked about the accuracy standard and testing procedure. They test fired some rounds from every batch out of a sort of benchrest gun thingy. The accuracy spec for SS109 was a 10 round group measuring no more than 30mm at 100m. Should be roughly around 1.2 MOA.
Just to make sure: M855 is the standard 62gr SS109 right?
I actually visited the Nammo plant (the big ammo producer here in Sweden www.nammo.com) a few years ago. I asked about the accuracy standard and testing procedure. They test fired some rounds from every batch out of a sort of benchrest gun thingy. The accuracy spec for SS109 was a 10 round group measuring no more than 30mm at 100m. Should be roughly around 1.2 MOA.
Yes sir.
How did the barrel fire before it was cut down?
Did you build it yourself? If so, how tight was the upper receiver to barrel extension fit? What you are describing, sounds like a loose barrel, especially if you get several rounds close to each other, then several fliers.
I actually visited the Nammo plant (the big ammo producer here in Sweden www.nammo.com) a few years ago. I asked about the accuracy standard and testing procedure. They test fired some rounds from every batch out of a sort of benchrest gun thingy. The accuracy spec for SS109 was a 10 round group measuring no more than 30mm at 100m. Should be roughly around 1.2 MOA.
Can I buy this wonder-ammunition in the USA?
How did the barrel fire before it was cut down?
Did you build it yourself? If so, how tight was the upper receiver to barrel extension fit? What you are describing, sounds like a loose barrel, especially if you get several rounds close to each other, then several fliers.
No idea. The barrel went straight to the gunsmith for cutting.
Yes, I built i myself. From what I can judge the fit was tight/good. In line with other uppers and barrels I’ve seen. If I dont try another barrel I’ll probably have a gunsmith look at the upper and see if he can find something.
I can emphasize with your disappointment. I built an upper once that hated my training ammo. I couldn't seem to get better than 4MOA with it, but it shot 77gr ammo incredibly well.
The Faxon is generally not a great quality barrel, and commercial M855 and 55-grain American Eagle are average to below-average (at best).
Seeing as you're in Sweden, have you tried one of the local commercial ball or match ammunition options? Perhaps Nammo or Lapua, or maybe an import like IMI, MEN, or Fiocchi?
I would disagree that Faxon does not make quality barrels. My personal experience with a Faxon 20" .308 barrel has been great. MOA with quality ammo. Still around 1.25-1.5 moa with 7.62x51 ball.
Thunderpigeon
08-26-21, 17:41
I would disagree that Faxon does not make quality barrels. My personal experience with a Faxon 20" .308 barrel has been great. MOA with quality ammo. Still around 1.25-1.5 moa with M193.
How do you shoot M193 out of a .308 barrel?
I would disagree that Faxon does not make quality barrels. My personal experience with a Faxon 20" .308 barrel has been great. MOA with quality ammo. Still around 1.25-1.5 moa with M193.
The older reviews are good but last year I got a bad barrel and the replacement was bad too. I don't think they handled the ramp-up in demand well. I hope they get QC under control again.
ViniVidivici
08-26-21, 17:49
I've read enough bad experiences by other shooters to not ever buy a Faxon barrel, myself.
How do you shoot M193 out of a .308 barrel?
Got me, I meant 7.62x51 ball.
I would disagree that Faxon does not make quality barrels. My personal experience with a Faxon 20" .308 barrel has been great. MOA with quality ammo. Still around 1.25-1.5 moa with M193.
You must be pretty darn good to get that kind of accuracy shooting 5.56 M193 out of a .308 barrel. Well done sir! :)
Why are you implying that the quality of Faxon barrels differs between 5.56 and .308? Do they come out of separate factories?
How do you shoot M193 out of a .308 barrel?
The case fire forms. :p
Wasn’t there a member here that worked for faxon. I think his name was Nate and if I remember correctly he went to another job, but maybe he knows someone that can help the OP or maybe faxon has another employee monitoring this forum.
The case fire forms. :p
Wasn’t there a member here that worked for faxon. I think his name was Nate and if I remember correctly he went to another job, but maybe he knows someone that can help the OP or maybe faxon has another employee monitoring this forum.
It is a bit unrealistic to ask a manufacurer to warranty a barrel that has been shortened by a third party based on accuracy results with non-match ammunition.
Like Red Lion, I had a Faxon barrel that shot quite well, but mine was a 20" Gunner in 5.56. Enough members here had issues with Faxon barrels that I would personally not buy another.
Andy
M193 and M855 generally shoot 2-3" groups in almost every rifle I own. Better in a few. They are certainly not match grade but also, certainly adequate for their purpose and probably the most common types of ammo available for the AR15. I wouldn't own a rifle that wouldn't shoot them reasonably well.
The older reviews are good but last year I got a bad barrel and the replacement was bad too. I don't think they handled the ramp-up in demand well. I hope they get QC under control again.
The crap barrel we dealt with was 4+ years ago i'd guess. ZERO chance I'd ever by any barrel from them ever.
In that case I hope someone else makes a 19 ounce 16" pencil barrel.
In that case I hope someone else makes a 19 ounce 16" pencil barrel.I've got a BCM pencil barrel upper. Not sure what it weighs as it's a factory rifle, but I imagine it's close to that.
16-ELW-F-STD (https://bravocompanyusa.com/bcm-standard-16-mid-length-enhanced-light-weight-fluted-barrel-stripped-625/) is the lightest one I see at 21.5 ounces. Close indeed, but still not a match for Faxon.
16-ELW-F-STD (https://bravocompanyusa.com/bcm-standard-16-mid-length-enhanced-light-weight-fluted-barrel-stripped-625/) is the lightest one I see at 21.5 ounces. Close indeed, but still not a match for Faxon.
They have a lightweight skinny barrel that's not an ELW. 19 oz.
ETA: https://bravocompanyusa.com/bcm-standard-16-mid-length-light-weight-barrel-stripped-625/
They have a lightweight skinny barrel that's not an ELW. 19 oz.
ETA: https://bravocompanyusa.com/bcm-standard-16-mid-length-light-weight-barrel-stripped-625/
The linked page reads "Approximate Weight: 1lb 7oz." That's 23 ounces.
The linked page reads "Approximate Weight: 1lb 7oz." That's 23 ounces.Oops. Sure does. Brain fart.
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