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Discussion Starter · #1 ·
I own a couple of commercial brands of bolt action chambered in the .338 LM. My question is why are both rifles of different makes come with a 1:9 twist barrels? The match bullets from Hornaday state on the box 285 gr and 309 gr for 1:10 twist or higher, does this mean I’m limited to the 250 gr for accuracy….or am I just looking at the issue inaccurately?
 

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I own a couple of commercial brands of bolt action chambered in the .338 LM. My question is why are both rifles of different makes come with a 1:9 twist barrels? The match bullets from Hornaday state on the box 285 gr and 309 gr for 1:10 twist or higher, does this mean I’m limited to the 250 gr for accuracy….or am I just looking at the issue inaccurately?
Depends on what you are going to shoot at . The match rounds are designed for match barrels which are usually 28 in or more so the higher number (slighter twist) put less drag on the bullet keeping the fps higher as it comes out of the barrel. 26 in barrel works fairly well.
 

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Use them both and report back the results. I use 250gr. Cutting-Edge, 250gr. Sierra MatchKing, 250gr. Hornady, and 285gr. Hornaday and get sub moa with my developed handloads. It took a lot of time and patience but success was achieved. I have used H1000, Retumbo, 7828, and H50BMG.... yes the powder H50BMG worked extremely well! I shoot my best with 250gr. Sierra Matchking BTHP.
 

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Discussion Starter · #4 ·
Thanks guys, the one I’m working on now has a 26” barrel, the problem is the first 2 shots touch and third is always 1/2” high, this is at 100 yard? I’ve tried different powders, bullet weights, an seating depths letting the barrel cool between shots and it makes no difference? The rifle came with the aluminum v block bedded in the stock, I put layout ink on it an found heaver on the rear right and the left front of the blocks so my next step is to cut them down and bed it? If that does solve the problem I intent to cut the rifle into 12” pieces and ship it back to the manufacture with a note about the flaws and old machinist found, the move on to the new rifle I purchased with a 27” barrel.
oh yea, my intentions are to shoot out to 1500 yards
 

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What do you do to restore the rifle to the first shot? Do you clean it, wait a day or two or what? If letting it cool for the same period doesn’t fix it the problem is in what ever you are correcting when you put it away. Is the barrel fouling?
 

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Discussion Starter · #6 ·
I have been shooting it at 100 yards on an indoor range. I shoot from an adjustable stand with a saddle type sand bag and a smaller bag under the rear. I have the stock marked where the are positioned, also use an adjustable cheek rest with tape on it to ensure I’m positioned the same place as well the pistol grip, trying everything I can to make sure the rifle is fired consistently? I have used the same 3 load using SMK 300 gr., Hordnady 285 gr. And 250 SM, Retumbo and H1000 is about I use. It doesn’t seem to matter if I shoot 3 in row, wait anywhere from10 mins to 1 hour between shots, I also use a laser temp gun to confirm the barrel temp is same for each shot. I don’t clean the barrel every shot but I do clean every 9 shots even though those group the same, I’m did not clean the barrel on my last outing so I will see how it does fouled. I am 73 years and I can only shoot it about 18 round per session due to the recoil, any more than that and the group starts walking to the right, I’m sure that me pulling rifle tighter to my shoulder trying to reduce felt recoil? I have been shooting since I was 13, shoot two.308s and a .300 WM I have done minor tuning on all 3 rifles and can still shoot consistent sub Moa. I know what your thinking…. If the shoot that good then why the .338 LM? I guess it on my bucket list, I would like to try some extreme distances before my health gets to the point I can’t shoot or travel?
 

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I own a couple of commercial brands of bolt action chambered in the .338 LM. My question is why are both rifles of different makes come with a 1:9 twist barrels? The match bullets from Hornaday state on the box 285 gr and 309 gr for 1:10 twist or higher, does this mean I’m limited to the 250 gr for accuracy….or am I just looking at the issue inaccurately?
If it is in 1:9 you're fine. Lower the number faster the barrel. At least that's what I have been taught.
 
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