DPMS UPPER WARNING / REVIEW

[yesjesusknows]

I purchased a 308 lower from 80% ARMS and finished the FCG by the way Great Product with a nice finish. All working items function well, magpul magazines work well and the DPMS lower parts kit is working well.. However my DPMS upper has a abnormal gap at the curve near the buffer tube or is it the lower? I spoke with 80% ARMS and sent them the photos of the issue. I was told that DPMS uppers are cut short at the problem area and that other brand uppers fit snug. My fellow calgunners don't buy a DPMS upper if you are using a different brand 308 lower... If anyone has any insight please share it or am I just tripping. Thank you

[jdmstuff]

80% is correct. The DPMS upper is undercut as I have the same gap between that upper and my JD Machine lower.

[evolixsurf]

Do all dpms uppers have this issue?

[cpl_dan]

I as well have an 80% arms 308 lower and i just got a dpms stripped upper and i mated them and i do have a little gap but not as big as the one in the picture.

[80% Arms]

This is normal and comes down to variances in the uppers, not the lower. The photo with a light shining behind it magnifies the gap, but none the less there is a small gap on DPMS uppers. Some DPMS uppers are worse than others, their QC seems a little inconsistent. The radius on DPMS uppers is a bit different than many other brands. If we widened up that radius on our lower to make the DPMS upper fit perfectly, our lower would not fit other brands of uppers. There are quite a few uppers that fit perfectly with our lower, CMMG being one example. Unfortunately there isn't a mils spec standard for .308 designs like there is for AR-15, so we have to build to a standard that functions with the widest variety of uppers on the market. On some brands there may be a very small gap back there, but the trade off is that our lower will fit all known DPMS pattern .308 uppers.

[cpl_dan]

something to share, somewhat helps determine what kind of 308 upper you have.

[1badjack68]

Tagged

[Whiterabbit]

to recap, the serialless, no 10 day weight, fraction of the cost paperweight you manufactured at home to be a gun has excellent function but all the quality fit of a mass manufactured aluminum semiautomatic gun, and that upsets you?

Why don't you just spray the upper with wax mold release and fill the gap with brownells glass bedding? serious question. Adhesion would be just fine, finish fixed via file, the lower would coat just fine, and you'd get a fit so fine as to be hand fitted because it was.

No reason to suggest the fit should be there to begin with, tolerance is in mass manufacturing (and I don't care about severity, tolerance is tolerance), and these aren't hand fit parts. No reason not to correct that if desired though, no?

[BMartin1776]

there are 2 dpms uppers which one did you get?

[VaderSpade]

All my Tactical Machining lowers match up perfectly with all my DPMS uppers.

I have several of both types of DPMS uppers (with and without dust covers).

[Whiterabbit]

I still don't know why this hasn't been solved with acraglass and recoating. It's good enough for the recoil lug of a safari rifle, it's good enough to solve fitment of an aluminum reciever.

[Gunsmith Dan]

I am sorry but it seems the OP is completely confused as it should be titled "DPMS UPPER warning" since it is the upper not the lower that is out of spec.

The OP stating that 80% ARMS is responsible to inform their customers which batches of UPPERs from all the different companies are out of spec and which batches are in spec is ridiculous.

That is like putting tires on your car and the tire manufacturer is responsible to list every single rim manufacturer and which rims made which dates would be in spec.

The OP seriously needs to change his title as he is slamming the wrong company.

[umd]

The OP seriously needs to change his title as he is slamming the wrong company.

Yeah, I mean DPMS can't even stick to it's own pattern...

[biglou]

OP did you contact DPMS and send them the same pics ? What is their response ?

[yesjesusknows]

Fellas thank you for all the detailed information. Everyone has a valid response and I do understand the 308 pattern a lot more clear than before.
I agree with whiterabbit I will fill in to resolve the fitment.

Also I know I came a bit strong on 80% ARMS and will change the title as Gunsmith Dan mentioned. I will be honest and say I thought the 308 pattern was some type of mil spec as the ar15 pattern.(That's what I get for thinking) also that's why I started this post to get some detailed insight from the community. I did post that the 80% ARMS lower is good and all functions are properly working. When I did get in contact with 80% ARMS they were quick to get back to me with the information and did not drag their feet on my concerns. I hope this will help out any fellow calgunners with their build as it helped me.

Biglou: Evolved has a valid post on this matter which has helped me and I was satisfied enough with it and did not pursue DPMS so no I did not contact them.

BMartin1776: I have the new low profile style upper