So I have a DPMS AP-4, that I may have fired a total of 100 rounds through it. My issue is that recently when I pull the charging handle back. I meet some extra resistance at about half way. Now I know that my bolt isn't properly staked on one side. I have also recently replaced the stock trigger with a timney drop in. If anyone has ideas as to what it could be I would appreciate any help.
-
Having trouble using the site?
Contact support
DPMS AP-4 and I got an issue
- Thread starter briantlegvold
- Start date
Re: DPMS AP-4 and I got an issue
Is the charging handle bent? Take it out and look at it to make sure it is ok first.
Is the charging handle bent? Take it out and look at it to make sure it is ok first.
Re: DPMS AP-4 and I got an issue
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: strangedays</div><div class="ubbcode-body">Is the charging handle bent? Take it out and look at it to make sure it is ok first. </div></div>
That was my first thought also.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: strangedays</div><div class="ubbcode-body">Is the charging handle bent? Take it out and look at it to make sure it is ok first. </div></div>
That was my first thought also.
Re: DPMS AP-4 and I got an issue
I would say that either the CH is bent or you have a lose bolt carrier key (since you already know it isn't staked properly).
I would say that either the CH is bent or you have a lose bolt carrier key (since you already know it isn't staked properly).
Re: DPMS AP-4 and I got an issue
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: EagleI79</div><div class="ubbcode-body">Lube...and lots of it. Or it bent. </div></div>YES on that one -get a steel one with gas redirect --also the gas key may need replacement as well /bolts are know to break if staked wrong -red high temp loctight and mojacks tool will save the day ......i have one too ....
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: EagleI79</div><div class="ubbcode-body">Lube...and lots of it. Or it bent. </div></div>YES on that one -get a steel one with gas redirect --also the gas key may need replacement as well /bolts are know to break if staked wrong -red high temp loctight and mojacks tool will save the day ......i have one too ....
Re: DPMS AP-4 and I got an issue
The hammer does contact the bottom of the bolt carrier and can sometimes cause significant friction.
Pull the trigger and hold it to the rear.
Now with the trigger held back, cycle the BCG.
Did the resistance lessen?
The hammer does contact the bottom of the bolt carrier and can sometimes cause significant friction.
Pull the trigger and hold it to the rear.
Now with the trigger held back, cycle the BCG.
Did the resistance lessen?
Re: DPMS AP-4 and I got an issue
Ok guys, sorry I've been in Fort Polk, La. for a month so getting back to all of you has been a challenge. I'm going to start looking into all these things tonight and let you guys know what I find.
Ok guys, sorry I've been in Fort Polk, La. for a month so getting back to all of you has been a challenge. I'm going to start looking into all these things tonight and let you guys know what I find.
Re: DPMS AP-4 and I got an issue
Swap out the trigger for the stock one and see if it still does it. Also check to make sure that the buffer tube is put on correctly (mine did the same thing when the buffer tube nut was loose, I assume you have a 6pos stock).
Swap out the trigger for the stock one and see if it still does it. Also check to make sure that the buffer tube is put on correctly (mine did the same thing when the buffer tube nut was loose, I assume you have a 6pos stock).
Re: DPMS AP-4 and I got an issue
take .030" off the edge of the hammer tip at the angle where it would be parallel to the bolt when in the cocked position.
take .030" off the edge of the hammer tip at the angle where it would be parallel to the bolt when in the cocked position.
Re: DPMS AP-4 and I got an issue
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BCP</div><div class="ubbcode-body">Swap out the trigger for the stock one and see if it still does it. Also check to make sure that the buffer tube is put on correctly (mine did the same thing when the buffer tube nut was loose, I assume you have a 6pos stock).</div></div>
that is what I was thinking - check the buffer tube and spring - is this a 223 or 308 APP4? Is it the correct spring set-up for a 223 or 308?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BCP</div><div class="ubbcode-body">Swap out the trigger for the stock one and see if it still does it. Also check to make sure that the buffer tube is put on correctly (mine did the same thing when the buffer tube nut was loose, I assume you have a 6pos stock).</div></div>
that is what I was thinking - check the buffer tube and spring - is this a 223 or 308 APP4? Is it the correct spring set-up for a 223 or 308?
Re: DPMS AP-4 and I got an issue
Ok, so the culprit was the hammer, which was contacting the bolt group when I charged it. Because I have a timmeny AR-10 trigger system in it. There is a lot less play in the hammer and the hammer is also larger. It turns out that pretty much all AR model rifles do this. It is just more pronounced on mine due to the stiffer spring. So my question now is, should I be concerned about this? Personally I think it is fine and I took it out on Friday and fired 60 rounds through it.
Ok, so the culprit was the hammer, which was contacting the bolt group when I charged it. Because I have a timmeny AR-10 trigger system in it. There is a lot less play in the hammer and the hammer is also larger. It turns out that pretty much all AR model rifles do this. It is just more pronounced on mine due to the stiffer spring. So my question now is, should I be concerned about this? Personally I think it is fine and I took it out on Friday and fired 60 rounds through it.
Re: DPMS AP-4 and I got an issue
Have you had any malfunctions on the Timney AR-10 Trigger. I am about to drop money on a DPMS .308 and have been looking at replacing the stock trigger with either a Timney AR-10, Chip McCormick or the Wilson Combat. I want a single stage an no srews or adjustments. I have heard mixed reviews on the Chip McCormick triggers but not much on the Timney AR-10 model or the Wilson Comabts. So please let me know how your Timney is working out and any problems
Have you had any malfunctions on the Timney AR-10 Trigger. I am about to drop money on a DPMS .308 and have been looking at replacing the stock trigger with either a Timney AR-10, Chip McCormick or the Wilson Combat. I want a single stage an no srews or adjustments. I have heard mixed reviews on the Chip McCormick triggers but not much on the Timney AR-10 model or the Wilson Comabts. So please let me know how your Timney is working out and any problems
Re: DPMS AP-4 and I got an issue
Two stage triggers:
Geissele Automatics DMR
Knights
These hold up in big chassis AR's.
Accuracy Speaks is a good single stage.
Two stage triggers:
Geissele Automatics DMR
Knights
These hold up in big chassis AR's.
Accuracy Speaks is a good single stage.
