Breck Posted September 22, 2015 Report Share Posted September 22, 2015 (edited) Hello,I just recently purchased a used DPMS SASS Gen 1. The guy I bought it from said he hadn't put more than 80 rounds thru it. He warned me that it doesn't like to fire anything under 180gr. Very clean and in great shape. I took it to the range today to sight it in. He was right. It would cycle 180gr ammo all day. Any time I tried to fire anything lighter, it would fire the round, eject the empty case, but fail to chamber another round. This leads me to believe that the bolt isn't going back all the way. Does that sound correct? The buffer spring is very tight but I'm sure it has to be for this heavy round.I was using a Gen3 Magpul 20rd magazine.My question is this: AM I doomed to only be able to fire 180gr or heavier ammo? Is there an easy fix that anyone knows about? Can I buy a lighter weight buffer?Any advice would be greatly appreciated. Thanks in advance,-Breck Edited September 22, 2015 by Breck Quote Link to comment Share on other sites More sharing options...
Sisco Posted September 22, 2015 Report Share Posted September 22, 2015 (edited) 80 rounds is still the break in period. It may loosen up with some more rounds through it. Be sure to keep everything really well lubricated during that break in phase. Does that model have an adjustable gas regulator? I am not familiar with it. If it does, make sure that it isn't partially closed. Also, did you and the previous owner always use the same Magazine? Just to rule it out, try a different one. I am going to get off and let more knowledgeable guys about this model weigh in. Edited September 22, 2015 by Sisco Quote Link to comment Share on other sites More sharing options...
edgecrusher Posted September 22, 2015 Report Share Posted September 22, 2015 I definitely wouldn't go lighter... Heavier. Slow the cyclic rate. I would hazard a guess the BCG is moving to fast to pick the new round up. Just a thought. Quote Link to comment Share on other sites More sharing options...
washguy Posted September 22, 2015 Report Share Posted September 22, 2015 Welcome to the forum Breck ! okay look on the top of the barrel...does it say x-caliber? ...... just kiddingSo if its a factory built rifle it will have a K in the lower's serial number if memory serves. I built a rifle with the super sass barrel and it ate every kind of ammo.So it may not be a factory rifle.. and the person that put it together it may have used the wrong parts,so its not cycling properly What stock? car stock? you need to check for the proper buffer tube,buffer, and buffer spring.....pics would be nice. You stated that the bcg is not going all the way back and the spring is tight...you need to take out the spring and buffer and measure the spring and the inside depth of the buffer tube...length of buffer... Wash Quote Link to comment Share on other sites More sharing options...
98Z5V Posted September 22, 2015 Report Share Posted September 22, 2015 (edited) So if its a factory built rifle it will have a K in the lower's serial number if memory serves.Backwards, brother. DPMS puts a K at the end of the serial number on stripped lowers, only. If it has a K at the end, it started life as a stripped lower, and not a full factory rifle. :thumbsup:There's either a gas system issue going on here, or a recoil system issue (weights of buffers, or spring rate/length).OP, need more details. LOTS of details. As in, list every part of the rifle. Pics help. Edited September 22, 2015 by 98Z5V Quote Link to comment Share on other sites More sharing options...
washguy Posted September 22, 2015 Report Share Posted September 22, 2015 Backwards, brother. DPMS puts a K at the end of the serial number on stripped lowers, only. If it has a K at the end, it started life as a stripped lower, and not a full factory rifle. :thumbsup:I knew there was a K Ha just back azzwords ...lol Wash Quote Link to comment Share on other sites More sharing options...
dbwalker Posted September 22, 2015 Report Share Posted September 22, 2015 sounds like the timing is out of wack, either cycling to fast "like edge said" or to slow, next time you go to the range watch where your shells are going, if their flying forward to 1 or 2 oclock it's cycling to fast, 4 or 5 oclock "rearward" = to slow, a simple remedy for to slow is get a lighter buffer, to fast = get a heavier buffer, another option if cycling to fast is to get an adjustable gas block so you can restrict the amount of gas the rifle needs to cycle properly, being that is working with heavy ammo & not lighter I would lean toward your buffer is to heavy & its not getting enough gas pressure to cycle the carrier, I've experienced both scenarios that you are having, the only difference is I dealt with them on AR-15 platforms, when I had the low pressure problem I ended up replacing the buffer & the gas block so that I could adjust the gas for different ammo Quote Link to comment Share on other sites More sharing options...
shepp Posted September 22, 2015 Report Share Posted September 22, 2015 I knew there was a K Ha just back azzwords ...lol WashI'm gonna have to take a look at mine now when I get home Quote Link to comment Share on other sites More sharing options...
survivalshop Posted September 23, 2015 Report Share Posted September 23, 2015 I have one of each , "K" & no "K" , the one with out the "K" was a complete lower assembly , the one with the "K" was a stripped Lower . Need to know if it was a DMPS Factory rifle or a build . Its short stroking with lighter loads , can be several things .-Not enough lubrication on a new rifle or Build ,- Rough or tight chamber ,-Gas Block incorrectly positioned or not sealing,-Gas port in Barrel , not large enough .-Carrier Key loose or not sealing ,-Something in Buffer system not to spec.,And the list can go on . Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.