anyone know how good these mags are for the M1A.have a chance to buy several & need to know of any problems with them. they will be range only mags if that helps

I have one (1).  Works in the M14, won't work in the M1A.  No clue why, but I've not spent any time on it.

-- Chuck

I owned three years ago. I bought them right after the AW bill hit us as the thermolds were still cheap. I had the same experience Chuck had. None of them worked in my Federal arms and one only worked in the one M1A while the other two only liked the other M1A. Buying thermolds is like a crap shoot- you never know what the dice will roll... BTY I got rid of mine... they just were not worth it. Try Coles or Sarco for used GI 20 rounders for $36.99.. you will be much happier.

CB and guys,

I bought 5 new Thermolds a few years back.  They all required "fitting" in order to work properly, but now work just fine in my M1-A.

The mag catch lug on the back edge of the magazine body had to be shortened on the bottom edge with a dremel cutting wheel.  As made, the lug is too long for the mag catch to ride over the end.  Just shorten it a bit at a time until the mag catch engages and you are fine.

Feed lips....  The feed lips are a bit oversized as well and drag against the bottom of the bolt.

Insert a mag, then work the bolt by hand a dozen times.  Remove the mag and inspect the lips for rub marks.  Slowly grind these areas back until you stop feeling resistance in the bolt.   At this point all should work well.

Best regards,
Swampy

thanks for the info everyone. I think I'll just pickup one and give it a try

They make great targets~~~stick with the USGI one's.  (Under $40 at Cole's)

 Over time the locking hole at the front of the mag will tend to stretch...at the point the mag begins to dip downwards and you will start having feeding problems....until then it will feed like butter or not at all.  One or the other.  I have several and I no longer use them.