I posted up in the general firearms section that Dunhams stores are having an ammunition sale.
The best buy I saw was Portugese 7.62X51 Mil-spec on Machine gun links and packed in 200 round cans for $44.95 a can, normally the stuff is $59.95 a can.
I bought two cans of the stuff.
Don't let the machine gun links fool you.
Almost all the 7.62 linked ammunition is the exact same stuff as Mil-Spec boxed or clipped in bandoleers.
High pressure, tracer, and the like goes to dealers who specialize in machine gun specific cartridges and the stuff is always noted as such and usually quite a bit higher in price than standard 7.62X51 ammunition.
As for slam fires in the M1A, they are more likely to be caused by trying to feed NATO specification ammunition into a commercial chamber than by too soft primers.
Commercial go headspace runs about 1.630" and NATO go headspace runs at about 1.636" on average.
Six thousands of an inch doesn't sound like much but it is enough to induce a slamfire if you try shoving hard, thicker cased NATO ammunition into a tighter, commercial chambered semi automatic.
Springfield and most other builders tend to split the difference and chamber the rifles to 1.634" which is actually commercial no go and just a bit tight for NATO but the length has been determined to allow a safety margin regardless of the type of ammunition used.
New Springfield Inc. rifles include a hang tag listing the actual headspace of the rifle.
If you are in doubt, have a gunsmith familiar with M14 rifles headspace the rifle to determine exactly what your chamber dimensions are.
Springfield has built a number of rifles, custom order, with tight commercial chamber dimension.
It is important if you buy a used M1A, or any M14 type rifle that you receive that headspace card or at least a certification from the dealer as to the actual headspace of the rifle.
If the dealer can't provide the info, pass on the rifle or bring your own gunsmith to check the rifle before you plunk your cash down.
If the dealer won't allow this, pass on the rifle, no matter how good the price may seem.
If allowed the gunsmith can check the weapon over and then advise you as to what ammunition is safe to fire in that particular rifle.
Unless a specific headspace is requested, I tend to build rifles with a 1.636" headspace since most of my customers shoot and reload NATO specification ammunition.
Commercial ammunition is more than safe to fire in a rifle so chambered but I do not advocate reloading the brass since case stretch in commercial brass tends to be excessive at these dimensions and reloading the cartridge cases more than once will usually cause case head seperations.HTH
