Are there any issues or pains with the current M1A platform compared to the AR (or AR-10) platform?
Last year I got a Colt LE Carbine and this year I got an M1A squad scout. Surprisingly the Colt was virtually trouble-free. But so far I'm having some teething issues with the M1A. The gas vent wasn't adjusted properly, so I got short stroking. After an additional turn of the locking ring that was fixed. Now after about 100 rounds some surplus 7.62 is sticking in the chamber, about every other round. And on examination the chamber is extremely rough with visible grooves. I'm not sure if that's on purpose but it most certainly has a clinging effect on brass.
Another problem--component and replacement costs can be VERY HIGH. Sometimes shockingly so. And there's a very aggressive market for them. I've been outbid on three stocks so far on GB, each one a tiger strip and going for over $200. Simple replacement parts which on a Mosin would go for a few bucks cost hundreds with the M1A. Old M14 parts seem to be highly prized and subject to auction wars. Everything seems to be high priced, perhaps because the users are older men with more money. And maybe also because there's less competition among suppliers than for AR's. I haven't done a side-by-side breakdown of extra costs on the AR vs. the M1A, but I know I spent less on the AR. Retro front hand guards, new rear hand grip. Winter trigger guard. A few odds and ends. That's about it. I've already spent a few hundred on various stocks for the M1A and I haven't even started revamping it in earnest.
On the positive side, I'm finding the M1A in its proper M14 stock with proper steel buttplate to be much more comfortable to shoot in the stances than the wobbly barrel-light AR carbine. I'm getting the best 100 year off-hand groups of my life with that rifle, using only a hasty sling.
But I do expect to have more issues as I work out the bugs. I expect to be doing a bit of chamber polishing, retrofitting it with some mil spec M14 parts, shimming and upgrading the gas system, and glass bedding a surplus stock.
In short, the M1A doesn't seem to be the best choice for those who like everything to roll without trouble from the first shot. It's a firearm for tweaking.
I also agree that the M1A shines with its fantastic irons--evolved from the Garand. They're probably the best irons on any rifle I've shot. Scopes can be used on them, but if you want high mag you're better off with a flat top AR pattern .308. Scoping the M1A, you lose some of the magic of it IMHO. I tried out my scout scope mount, didn't like it and won't be using it again.
Another nice point is that if one stock doesn't work for you, swapping out is real fast and simple. There may be some point of impact change of course, but for example if you find that one stock is too thin in the wrist you can get a "big red" birch stock and fix that issue. Bedding makes it a bit more tricky, of course. I'm going to do my first bedding job on a beater, because the task is rather more complex than it is for a simple bolt action.
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