FGMM .308 verses 7.62 COAL

BattleAxe

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Recently I've been researching the idea of more custom loads than just shooting factory FGMM and I noticed that several ammo makers will specify a COAL of say 2.80.

Out of curiosity I have some FGMM .308 168's and FGMM 7.62 175's and I measured the COAL and the .308's measure 2.80 but the 7.62's measure 2.81

Ever notice this?
 

BattleAxe

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Re: FGMM .308 verses 7.62 COAL

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: tylerw02</div><div class="ubbcode-body">That's very likely normal variance... </div></div>

I thought that might be the case but I measured several rounds from several different boxes and the 7.62's are longer.
 

MD2Colo

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Re: FGMM .308 verses 7.62 COAL

just an fyi on the 7.62x51 stuff-
the last bunch of my M118LR from 08/09 measured COAL 2.812-2.815.
 

BattleAxe

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Re: FGMM .308 verses 7.62 COAL

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MD2Colo</div><div class="ubbcode-body">just an fyi on the 7.62x51 stuff-
the last bunch of my M118LR from 08/09 measured COAL 2.812-2.815.
</div></div>

Same here. When it was available I picked up a few cases of the Federal M118 in the white box and still have some. It also measures 2.81 and I had long suspected that the 7.62 GMM that Federal started offering after that supply dried up was the same stuff. Whether it is or not I don't know but the COAL is interesting and I'm wondering what the significance is.
 

DMack

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Re: FGMM .308 verses 7.62 COAL

Very interesting...

I have noticed that my PWS MK114 really, really likes the 175 SMK over the 168 grain SMK... and it prefers the M118LR over the 175 FGMM in .308

I've long suspected that the 175 grain got the round tighter in the leade than the 168... but, I am a newbie when it comes to reloading. I have not measured the difference. I have a few boxes at home, I will measure them tonight, in comparrison to the 175 FGMM in .308

I will give you a call later.