- Thread starter mpj76a
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My AI-AT really likes the Federal GMM with 168 gr SMK. It's good for 1/2 moa.
What are you experiencing?
What are you experiencing?
I just took this new rifle out for the first time today. I used the Hornady 178 gr and 195 gr ELD ammo, along with some federal 180 gr Triple shock.. Shooting off a bipod and monopod, my 5 shot groups ranged from .9 to 1.2 MOA at 100 yds which I thought was a bit meh. I didn't wait too long between shots and it's been a while since I've shot but still... I was hoping for around .5 to .75. I'm used to getting .3 to .5 MOA 10 shot groups with my .308 TRG 22 using FGMM 168 or 175 gr. All my screws remained torqued to spec. for barrel bolt and scope rail/rings. Most flyers were like WTF is going on here? I did have one Hornady 195 round that felt hot. That one strayed 2" higher than the group and resulted in a very hard to open bolt.
Something else I thought of is you might try re-seating your barrel if you haven't ever loosened it and then tightened it.
This...
I’m seeing about 1 moa center to center with my .300 win mag with federal SMK... about 1/2-3/4 moa with Berger and Hornady
6.5 cm barrel shoots much better 3/4-1moa with American gunner. And 1/4-1/2 moa with Berger’s
I did this prior to shooting it the first time. I'm assuming it just goes on hand tight, right?
I'll have to look. It's a brand new gun with facotry barrel, elite sand if that could denote newer/older since that's a newer finish.
Yes, basically. I like to take a run at the point where it tightens and hold it there for a few seconds. Then tighten the pinch bolt.
I'm not sure what you guy's are doing, except maybe you're just getting into shooting ?
, but only after 4 shots on a brand new barrel, my AT was smoking out 1/4-5/16 groups, with factory Hornady 168-178 match. And that day I was in a hurry to get it on paper so I could take my momma out to dinner....and that was at 200. AI's are bar none, top tier, crazy accurate factory rifles
Start shooting more ?
, but only after 4 shots on a brand new barrel, my AT was smoking out 1/4-5/16 groups, with factory Hornady 168-178 match. And that day I was in a hurry to get it on paper so I could take my momma out to dinner....and that was at 200. AI's are bar none, top tier, crazy accurate factory riflesStart shooting more ?
I'm not sure what you guy's are doing, except maybe you're just getting into shooting ?
Start shooting more ?
"I'm not sure what you guys are doing"
Other than the OP everyone is reporting 1/2 moa are you giving us a pep talk over 1/2 moa groups being unsatisfactory?
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On the AI's I have found that seating depth makes a BIG difference in group size. On my AX338LM running the 285 ELDM it is right at .012 off the lands and my AX308 is about the same running the 178ELDM. I would start at about .010 to .020 and I bet that you will find the sweet spot for you rifle.
This ^^
I was simply pointing out, that it's definitely not, probably not, the rifle ?
BUT.... I still could've been I suppose ??? (couldn't find a cheerleader, so you got a stadium and 2 golds)
Don't be a smartass.
This is the first five rounds I fired from my .300WM barrel, which had 400 rounds on it when I got it. I was shooting Hornady 178 gr. ELD Match at 100 yards. Not only is that the best group I’ve ever shot with my AXMC, but that point of impact represents the offset from my .308 Win. zero. I was amazed. It’s still the best shooting barrel I have. I very rarely shoot groups, and I don’t shoot .300 WM very often, so I don’t know what the average group size would be at 100. At distance, it’s usually sub-half minute, and if it’s not, I know it’s not the rifle. I said all that to say this; I would get a known competent shooter, with magnum experience, to evaluate the rifle.
I usually shoot 308 bolt action and semi. Sometimes 50 BMG bolt action. This rifle is heavy and shoots softer than the AR 10 pattern semi I shoot .75 MOA with. My typical 308 bolt group is .3 to .5 MOA. All factory ammo. Maybe it was just a bad shooter day like some have said. Ill try again with the FGMM when it gets here. Barrel markings are AI and W with a four digit number.
1) I wouldn't shoot for groups using a monopod, especially on a magnum. Switch to a good rear bag.
2) Recoil management makes a big difference with a magnum (see #1 above). I shoot an AXMC 338NM a lot, and if I get lazy on recoil management it will show up in group size. I can tell by how the rifle reacts and where the crosshairs go during recoil whether or not I'm at
fault. In the pic below, I was rechecking zero with a known-performance handload. Six shots, back to back. The first three at the center bull did not meet the proven performance level of this load, but I could tell I was not managing recoil well even though the zero was pretty good. So, I completely rebuilt my position on the bench, slowed down, and concentrated on fixing my fundamentals. The next three shots at the lower left bull show the difference. 0.657" vs 0.115".
Disclaimer: Yes, I know they aren't 5-shot groups. I was only checking zero, not load testing (it's a known and tested load). But the point isn't to demonstrate or brag on the rifle's performance here, but rather to show the difference that identifying and fixing your faults can make. The problem here was definitely not the rifle or the load. I shoot 338s extensively but anyone can get lazy or have an off day. Experience with the rifle allowed me to feel and see that I was letting the rifle exploit my weakness in position. You have a new rifle that you aren't as familiar with, so it may be more difficult to identify until you get more time behind it. Plus, I think the monopod is an added challenge that you don't need to be trying to overcome when you're trying to establish load performance right now. It is likely skidding/chattering on the bench surface during recoil (if you're on a bench), and regardless it doesn't have the lateral stability of having the toe of the stock bedded down into a good, solid bag. Try a good rear bag instead, and concentrate on fundamentals of recoil management, being brutally honest with yourself in your assessment of what you see happening through the scope throughout the recoil impulse. If still in doubt, as already suggested, let someone else with good magnum experience give it a whack.
2) Recoil management makes a big difference with a magnum (see #1 above). I shoot an AXMC 338NM a lot, and if I get lazy on recoil management it will show up in group size. I can tell by how the rifle reacts and where the crosshairs go during recoil whether or not I'm at
fault. In the pic below, I was rechecking zero with a known-performance handload. Six shots, back to back. The first three at the center bull did not meet the proven performance level of this load, but I could tell I was not managing recoil well even though the zero was pretty good. So, I completely rebuilt my position on the bench, slowed down, and concentrated on fixing my fundamentals. The next three shots at the lower left bull show the difference. 0.657" vs 0.115".
Disclaimer: Yes, I know they aren't 5-shot groups. I was only checking zero, not load testing (it's a known and tested load). But the point isn't to demonstrate or brag on the rifle's performance here, but rather to show the difference that identifying and fixing your faults can make. The problem here was definitely not the rifle or the load. I shoot 338s extensively but anyone can get lazy or have an off day. Experience with the rifle allowed me to feel and see that I was letting the rifle exploit my weakness in position. You have a new rifle that you aren't as familiar with, so it may be more difficult to identify until you get more time behind it. Plus, I think the monopod is an added challenge that you don't need to be trying to overcome when you're trying to establish load performance right now. It is likely skidding/chattering on the bench surface during recoil (if you're on a bench), and regardless it doesn't have the lateral stability of having the toe of the stock bedded down into a good, solid bag. Try a good rear bag instead, and concentrate on fundamentals of recoil management, being brutally honest with yourself in your assessment of what you see happening through the scope throughout the recoil impulse. If still in doubt, as already suggested, let someone else with good magnum experience give it a whack.
I had issues with my factory AXMC338 when I first got it. I tried several different bullets and probably fired 250rounds trying different powder charges and seating depths. Best I could do was 1.5" at 100yds.
Called AI, they wanted me to buy factory Lapua 300gr ammo and try it because that is what they test with. That shot 1.5moa as well. They took the gun back, placed a new barrel that was also a heavier contour, and now it is a .5moa gun. I just had a church group out to my private range this past weekend, and guys that had never shot a gun before were drilling the 1,400yd target with it.
Called AI, they wanted me to buy factory Lapua 300gr ammo and try it because that is what they test with. That shot 1.5moa as well. They took the gun back, placed a new barrel that was also a heavier contour, and now it is a .5moa gun. I just had a church group out to my private range this past weekend, and guys that had never shot a gun before were drilling the 1,400yd target with it.
I use the AI mono pod all the time for shooting groups and targets. The way that the rear is cut out on the AX338 it makes it difficult to use a rear bunny ear bag...I guess it could be done with a small squeeze type of bag but I prefer the mono pod. 
Loosened and re-tightened the barrel. Locked the hex screw using torque wrench. All scope screws good too. Finally got to shoot the FGMM 190. Used the bipod and monopd like before to make it a somewhat better apples to apples comparison. POI from prior range session didn't change at all which was cool. Five shot group sizes varied from .4" to .6". All were strung side to side which is nice since I could see my heart beat moving the reticle side to side. I'm happy.
Now...
I bought this 300 win mag long action with the intent of mostly shooting .308., so I'm looking for a 20" 308 barrel. I realize most top tier barrels are probably very close these days. That being said which is the "most" accurate? Right now I'm looking at AI, and proof carbon or stainless. Thoughts? Ammo used will be FGMM 168 or 175. If it shoots as good as my TRG 22, I'll sell it to streamline the collection (and keep wife off back).
Now...
I bought this 300 win mag long action with the intent of mostly shooting .308., so I'm looking for a 20" 308 barrel. I realize most top tier barrels are probably very close these days. That being said which is the "most" accurate? Right now I'm looking at AI, and proof carbon or stainless. Thoughts? Ammo used will be FGMM 168 or 175. If it shoots as good as my TRG 22, I'll sell it to streamline the collection (and keep wife off back).
Unless it has British proof marks on the barrel than it should be ours if it came from AI here in the States.
Box ammo can vary a ton even from the same maker. I’ve seen box Federal GMM 308 where one lot would give .8 to 1moa and another lot 1/3moa.
Cut rifled barrels on average last longer than a button/hammer forged rifled type barrels. That’s not just me claiming it....that’s data back from ammo/bullet makers, gov’t testing etc...
Later, Frank
Bartlein Barrels
Box ammo can vary a ton even from the same maker. I’ve seen box Federal GMM 308 where one lot would give .8 to 1moa and another lot 1/3moa.
Cut rifled barrels on average last longer than a button/hammer forged rifled type barrels. That’s not just me claiming it....that’s data back from ammo/bullet makers, gov’t testing etc...
Later, Frank
Bartlein Barrels
I’m getting 1/3 moa with the FGMM 190gr SMK.
the limit is me.
the limit is me.
If you bought the AI rifle new....from like Mile High etc...and the barrel is marked AINA than it should be our barrel. AI/Win Tactical buys blanks from us and they do the thread and chamber work etc...and install it on the rifle when it ships.
Some places might make a AI replacement barrel and do they’re own work but that doesn’t mean it is ours per say.
If you buy a replacement barrel from like Mile High just ask who’s blank they are using so you know what your getting.
Does that help?
what is the OAL with the 285gr eldm?
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