The difference between an M-14 that will consistently shoot 2" and one that will consistently shoot 1" can be THOUSANDS of dollars. Is 1" smaller groups worth that much to you??
I've had a few M1A/M-14/M-305 rifles that had almost every possible tweak known to man, no expense spared. One was a SA Super Match with SS barrel and Macmillan glass stock, another was a SA National Match in bedded walnut, another was a hand built SA HVY barrel, and another was a hand built Polytech receiver with all GI parts. All of these rifles shot about 1 1/4" 5 shot groups @ 100 yds with their favorite loads. The best 100 yd group I've personally seen from an M-14/M1A/M305 was 10 shots of 168 GR HPBT into 3/4". This was from a mildly accurised TRW M-14 I'd built for an ex-Brit sniper, and was shot with IRON sights. My personal best group with these type of rifles would be about 1" - 1 1/8", again shot from a mildly tweaked Chinese/GI Bastard I built from scratch, off a bipod, with a 24X scope.
I've also had literally DOZENS of the M-14/M1A/M305 type rifles, in fact nearly every one I've seen, that would shoot under 2" with the load they liked best. This may have required some inexpensive tweaking. Some of these rifles would do 1 1/2" with CHEAP Hirtenberger 7.62 NATO BALL. SO, what more do you need?
Keep in mind that many CHEAP bolt action .308 Rifles, such as the Rem 600, Rem 788, Savage 110 etc can be found that will shoot sub-MOA with NO tweaking, at a cost much less than some of these M-14 accessories or replacement parts, that won't shrink your groups more than a few fractions of an inch.
Spend your "accurising" money on trying out lots of different brands/types of ammo to see which ammo YOUR rifle likes best. The M-14 type of rifles are incredibly ammo sensitive, and groups can vary in the same rifle from 4" to MOA with the right ammo. And don't be surprised if you find one load that shoots near MOA in your bone stock M305. Try this before spending all sorts of CASH on tweaks you may not need.
BTDT ... [;{)
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