View Full Version : Tactical Machining AR-10 build questions

06-28-2012, 8:04 PM
Looking to build an AR-10 from Tactical Machining, possibily from an 80% lower. First thing I noticed is the TM upper doesn't have a bolt forward assist. Anyone here have any experience with these lowers and uppers?

06-28-2012, 9:46 PM
A lot of dpms 308 uppers don't have nor do they need forward assist.tmi have a TM lower and dpms upper and it shoots quarter sized groups at 100 yards if I do my part. TM is gtg.

06-28-2012, 10:09 PM
I'm of the opinion that the large frame AR's really don't need the forward assist. The bolt carrier is pretty massive in these compared to their 5.56 conterparts, and the spring pressure is much higher. It's either going to chamber, or you have more serious issues than can be solved with a forward assist. Having said that, I do tend to use the forward asist on my 308 AR's not so much to fully seat the round, but just to quickly check to ensure it's fully chambered before I squeeze the trigger. Kind of a bad habit I've picked up from shooting the DPMS SASS barrel with it's insanely tight chamber....

06-29-2012, 9:23 AM
foreward assists are not needed on .308 ar's due to the shape of the cartridge. For the most part they are not needed on ar-15's either

06-29-2012, 9:26 AM
Just to be clear for the OP,

Tactical Machining are NOT AR-10 format,

Tactical Machining are DPMS format (LR308)

06-29-2012, 9:53 AM
I swapped a TM lower on my DPMS TAC 20 to make it CA legal (bullet button added too). My point is that some of the spring recess channels are not exactly the same as the original DPMS lower. This is not a big deal as alternative springs and/or a plug can be used to achieve the desired results. The fit and finish of the TM lower is good quality and my gun (not weapon system) continues to operate flawlessly.

06-29-2012, 11:58 AM
the dpms bolt carrier i have doesnt even have scallops machined into it for the FA to push on it! Like others have said ya really dont need it, the TM lr308 upper receiver looks really nice, i woulda got that instead of the dpms upper in a heartbeat if it was available.. hmmm anyone want to buy my Dpms lr308 upper receiver so i can upgrade?

06-29-2012, 4:07 PM
Forward assists on 308 AR's are a joke don't worry about it.

06-29-2012, 4:40 PM
thanks for the replies!