View Full Version : Lowers and uppers

January 24, 2010, 09:23 PM
How much impact does the lower assembly of a AR have on accuracy, I would think that the firing and action is contained in the upper. Any thoughts?

January 24, 2010, 09:30 PM
Well, for starters, as the trigger group is in the lower and the bolt carrier in the upper... a decent fit between the two is kinda nice for the consistency of a repeatable firing pin/primer strike. ;)


January 24, 2010, 10:03 PM
The differences in performance between two quality lowers mounted to one upper are negligible.

Tucker 1371
January 24, 2010, 10:05 PM
quality lowers

Who makes a quality lower? I was considering buying a CMMG complete lower in a few months.

January 24, 2010, 10:12 PM
Stag, Mega, LMT, CMMG, DPMS are a few stripped lowers that are good. Hard to go wrong with most stripped lowers. It's the parts inside and the stock where the real quality differences begin to emerge.

You might check here first:

Generally, the Stag LPK is considered better than the DPMS LPK. Not necessarily the best LPK, but better than DPMS.

January 25, 2010, 02:48 PM
Basically, very little effect.

DSA has lowers for $60.

January 26, 2010, 02:51 AM
I agree. Mechanically, if you can reproduce each shot in the exact same way- it wouldn't matter if you had a major rattle-trap for a lower. Now, to get all your shots off the same- a tight fit between the upper and lower would be desirable. And to enhance that, a trigger group that allows a strike to the firing pin WITHOUT undue stress/movement/jerking of the trigger is another addition to what ever accuracy the upper and ammo can support.

While they were by no means benchrest or match quallity rifles- I've seen some M16A1's and a few A2's that were amazingly loose and sloppy BUT they still were able to deliver great groupings. This was because the lower (however loose) did it's job of holding the upper up so the shooter could allign the sights, actuate the trigger, and do it all again several times.