Things I've noticed reloading for 338LM

dstewart51

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Some entries out of my notebook.

-With new Lapua brass, Federal GM215M primers do not seat below flush. Must use primer pocket uniformer.

-Compared 50x 300gr Sierra SMK's to 50x Lapua 300gr Scenar's. Found the SMK's to have tighter tolerance in weight and diameter. The SMK's stayed closer to 300.0gr where the Scenar's where 299.9 and varied more. The SMK's dia stayed very close to 0.3379" where the Scenar's stayed near 0.3382". Just found that interesting.

-Hogdon Retumbo, burns very dirty, groups sensitive to charge, accurate but only near max charge. Random stuck cases even when the charge does not show any other pressure singes and well under max charge?

-VV N-570, burns cleaner (leaves grey graphite residue but it wipes off the case neck), not as sensitive to charge, very consistent groups, best groups just under max charge, no pressure signs even at book max. Never a stuck case or stiff bolt! Makes a nice crunching sound when seating bullet with a full case. Easy to achieve 2800+ fps with 300gr projectiles.

-Reddings Comp seating die RULES! Reduced my run-out significantly.

-A concentricity gauge is cool for about the first 5 min. After you get a Redding Comp seating die it's only a short matter of time before your realize you dont need it.

-Expander balls are great for fixing dented brass after it misses your hand and hits the concrete floor. Otherwise if you have proper bushing neck die, they are not that useful.

More to come...
 

mavrick10_2000

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Re: Things I've noticed reloading for 338LM

Fed primers have slightly larger cups, they will be a very snug fit in new or brass only fired a few times, unless you're pushing pressure.

What are you using to seat them? A hand press? Use something with a little more leverage if that's the case - they will be snug but sit below flush - unless new lots have shallow pockets.
 

Hoverp

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Re: Things I've noticed reloading for 338LM

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: dstewart51</div><div class="ubbcode-body">Some entries out of my notebook.

-With new Lapua brass, Federal GM215M primers do not seat below flush. Must use primer pocket uniformer.

-Compared 50x 300gr Sierra SMK's to 50x Lapua 300gr Scenar's. Found the SMK's to have tighter tolerance in weight and diameter. The SMK's stayed closer to 300.0gr where the Scenar's where 299.9 and varied more. The SMK's dia stayed very close to 0.3379" where the Scenar's stayed near 0.3382". Just found that interesting.

-Hogdon Retumbo, burns very dirty, groups sensitive to charge, accurate but only near max charge. Random stuck cases even when the charge does not show any other pressure singes and well under max charge?

-VV N-570, burns cleaner (leaves grey graphite residue but it wipes off the case neck), not as sensitive to charge, very consistent groups, best groups just under max charge, no pressure signs even at book max. Never a stuck case or stiff bolt! Makes a nice crunching sound when seating bullet with a full case. Easy to achieve 2800+ fps with 300gr projectiles.

-Reddings Comp seating die RULES! Reduced my run-out significantly.

-A concentricity gauge is cool for about the first 5 min. After you get a Redding Comp seating die it's only a short matter of time before your realize you dont need it.

-Expander balls are great for fixing dented brass after it misses your hand and hits the concrete floor. Otherwise if you have proper bushing neck die, they are not that useful.

More to come... </div></div>

Great info, I am going to get some N570. How is it supposed to do in temp variations compared to H1000? What grain wt worked best for you?

also what is your COAL with the bergers, are you mag loading or single?




Thanks!
 

JimGnitecki

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Re: Things I've noticed reloading for 338LM

dstewart51: I'm subscribing to this thread, as I just bought a TRG 42 in 338 Lapua, and will be devloping my own load soon, using Lapua cases and probably Vihtavuori powder (N560 or N570?) and moderate loads for long case life and for accuracy.

Keep it coming.

Have you tried primers other than Federal 215?

Jim G
 

dstewart51

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Re: Things I've noticed reloading for 338LM

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Hoverp</div><div class="ubbcode-body">
Great info, I am going to get some N570. How is it supposed to do in temp variations compared to H1000? What grain wt worked best for you?

also what is your COAL with the bergers, are you mag loading or single?

Thanks!</div></div>

I dont have enough data to comment on N570 and temp. What I did notice is it didn't seem sensitive to charge. It shot well from 90-93gr. My best groups came in at 91.5gr and 93gr (91.5gr was the best). So Im going to center around 91.5 and play with seating depth.

I have not done so yet but I have several lbs of H1000 and a few others to try, Reloader 25 and US869 on my shelf.

Only tested SMK's and Scenars so far. One thing at a time. Last thing I need to do is throw in another bullet to multiply the possible combinations. Once I have loads worked out for the SMK's and Scenars Ill give the Bergers a go. Right now, with both the SMK's and Scenars I have Mag clearance even if loading at the lands.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JimGnitecki</div><div class="ubbcode-body">

Have you tried primers other than Federal 215?

Jim G</div></div>

No, I buy my primers in bulk (5,000 at a time) and have standardized on Federal Match primers. All of my loads, hand gun and rifle use Federal Match primers. Helps keep things simple.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Mark S</div><div class="ubbcode-body">Can't comment on anything but fed primers, not a problem in my lot of lapua.</div></div>

As BossBoss915 mentioned here,
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=3030854#Post3030854
It seems the edge of the primer cups is resting on the inside radius of the brass. Like mavrick10 said above, the fed primers seat a bit deeper in my brass that has been fired 3 times.

Even with the seasoned brass I noticed the uniformer removing material from the outside radius well before the center near the flash hole.

I found this to be true with three lots of Lapua brass.