DPMS 260 issues?

[Broz]

Let me start off by saying this thread is not ment to be negative toward the company. But instead I would like to hear of any experience you have had with these rifles, both good or bad.

Here is our story. A good friend of mine purchased a 260 DPMS new and asked me to assist him in scope mounting and break in. So we mounted a 3x10x50 Lupy on it ran a couple dry patches through the barrel. Bore sighted and off to the range. First shot did not feed the second so I picked up the brass to examine it. Primer pocket blown out, primer gone, HUGE ejector marks. This was factory Federal ammo. I inspected the rifle and ran a patch down the barrel. Then opened a second box of Federal factory ammo and loaded one of them. This one the primer stayed in, but still HUGE ejector marks. At this point we stopped and went home.

I called DPMS and was greeted by a gentleman that was not seeing the issue. I then said, " we have a potentialy hazardous condition here" and he went to talk with someone else. When he returned he instructed me to remove the top 1/2 of the rifle and send it and the bolt in for them to repair, and also to include the fired brass.

That was 4 weeks ago............. It will be two weeks tomorrow since the rifle owner called and asked what they had determined. He was told it was going out today..... we have been waiting. I just called for another update and to ask if they new what was causing the issue. They said all they knew was it was blowing out primers and had ejector marks on the brass. I said that is the info I sent with it. I then said, can we get an accurate ETA? Hunting season is upon us. He took my number and said he would call me back today or tomorrow. So I will update this when I hear from them.

I hope my opinion changes, but at this point I am a bit less thas impressed.

Jeff

 

[ICANHITHIMMAN]

Good company, outstanding products

I dont know what the issue is I own about 4 AR's and have served in the MIL for 9 years and have never heard of a issue like this. In the AR weapons systems FTF issues are allmost allways attributed to the Magfollower.

I like DMPS they make a good product. I did not talk to the guy on the phone but I would call back and hope to get someone else if it were me.

Other things it could have been are the wrong recoil buffer and spring assembly.

Short recoil spring.

The chamber could have been dirty or had meatal shavings in it.

The barrel not might not have been tourqed to spec.

I know they shoot 10 rounds at the factory for civilian weapons and 30 for LE.

It could be the ammo to.

 

[Broz]

Yep, it could be the ammo too. But if so it is from two different boxes of factory ammo.

Chamber was clean and we run a couple patches through the barrel to make sure it was clean too.

Would tight head space do this? I don't know? I am not a smith, so we will see if they return my call tomorrow.

I have heard great things about these rifles. But right now the only thing I am sure of is they have had a returned NEW rifle for a month and have not touched it.

Jeff

 

[redbone]

The DPMS AR 10 Is the Same as the Bushmaster .

DPMS Bought out Bushmaster AR 10 Set Up .an All of There Tools To make hte AR 10 .

Terry

 

[britz]

DPMS has an excellent reputation for building a very good AR rifle. I live about 15 minutes away from the shop yet if I was going to buy one, I'd go to a local dealer because DPMS is booked out for a few months. They are very busy fillingLE and large shipment orders from what I can tell.

 

[Gary Kaney]

Just for what it's worth. I ordered a 308 back in Feburary, and all i know is that it's in the flow of things somewhere. This will be may second DPMS rifle.

 

[ICANHITHIMMAN]

I dont think a short chamber would cause this. I do think a slam fire would however. There is a small possabilty that you had a slam fire the firing pin punctured the primer before the round was seated and the lugs had rotated into battery. This would cause the primer to blow out and the extractor to chew up the case rim and the weapon to malfunction. There is allot of force put on the case by an auto loading rifle. Make sure your budy hits the forward assist with his palm apon chambering the first round.

The military uses diffrent primers in there ammo than are used in hunting ammo. The cup of the primer is allot stronger on military ammo thus eliminating the chance of a slam fire.

I use CCI #34 primers in my auto loaders.

I am not saying this is what happned but it would explain it from the info I have. You said the ammo was from 2 diffrent lots but not 2 diffrent manufactures right?

I was also wondering why you ran dry patches and not wet through the bore before you shot the weapon?

 

[Broz]

As far as the dry patch, I just wanted to make sure there was nothing in the barrel. The rod and patches were there and Just making sure of no grit or obstruction. Just a quick check.

They were not slam fires. We played with the rifle first and forward assist was needed to close it even with out a round chambering. So we did use the forward assist. I will add only these two rounds were fired. At first my friend loaded 3 rounds. When I seen the first case was destroyed we unloaded it and then decided to try a round from another box of ammo. For the second shot, only one round was chambered and again fordard assist was hit. Primers were not pierced. first was blown clear out of the case. Second was still in but case had all the signs of over pressure.

Ammo, Federal factory ammo. Same load two seperate boxes. Might be the same lot, didn't check. This may be the ammo's fault. That remains to be seen. Mark at DPMS said he would call me back either yesterday or today becaused I asked for an update on when we can expect to see the rifle back or what if anything they found. 4:00 pm here, still waiting.

I am not down on this company nor am I trying to bash them. I am just sharing the issue and looking for input. We either need to get this rifle fixed or replace it. Season is apon us.

I am only stating facts. Maybe we are to anxious?? But I think no matter who owned it after shelling out the beans for a new rifle anyone would like to get to the bottom of this asap.

Icanhithimman, I do appreciate your input. If it is the ammo I will report that here too, and contact Federal. What about a tight bore??

Thanks! Jeff

 

[ICANHITHIMMAN]

I should not have said peirced. I only ment they had been struck by the fireing pin and the round had gone of before the rifle was in to battery all the way might have only been 1 0r 2 thousands of an inch.

It is NOT normal to use the forward assist on an empty chamber! Your barrel nut could have been over tourqed.

I do not think a short chamber would explain this a pluged or missaligned gas port would might explain the overpressure. But the over pressure you decribed sounds like allot I know the use GO/NOGO guages at the factor to check headspace and fire the weapon 10 times. They use factory ammo and if there were a short chamber the weapon would not have passed through the doors of there factory.

I feel your pain on the fact that your bud dished out all that cash for a rifle to hunt with. I think DPMS should do some thing ASAP to make sure they are not letting out bad weapons.

 

[Broz]

I wish I had another 260 to fire some of this ammo and read the signs. That could tell us something. But yes, You had to let the bolt slam shut or it didn't close all the way even with out a round. If you let it go from 1/2 way it held open 1/4" or so but it easily shut with the forward assist. I just figured it would smooth up after a few rounds.

I have reloaded for over 20 years and I have crossed the line on pressure before. So I am confident we this was an over pressure condition. I just don't know what caused it.

The first time I called I wanted a factory ammo recomendation thinking they may have a light favorite load for accuracy. The guy I talked to could not give me one.

If they fired it ten times...????,.... Well I don't know about that. Unless the guy I keep getting on the phone tested it.

Jeff

 

[Broz]

Well, I promised an update. Here are the facts.

We got the rifle back, it took about 5 weeks and 4 or 5 calls. It returned with a paper stating this as the repair.

Chamber too tight. Polish chamber and test fire 10 rounds. Cycled well.

Those are not the exact words but close.

So my buddy brought it over, we remounted the scope and bore sighted it. I did a thorough bore clean and chamber clean. I was not going to be able to go shoot with him so he bought some remington ammo like they recommended and used at DPMS.

It cycled and shot well. But I still am not liking what I see on the brass.

Here is a pic of one of the fired cases. It is hard to show in a pic, but I think you can see that the primer is slightly cratored and flattened. Also brass is pushed into the ejector pin hole and is smeared as it is rotated during ejection. That is evident on both sides of the "M". I expect this to be worse with the Federal ammo. We will try some of it soon.

Am I being to picky?

Jeff

 

[ICANHITHIMMAN]

I guess you were on the right track all the time then. I just did not think a tight chamber would do that. I have learned someting from you on this one . Glad to hear your bud got his rifle back too. I will go look at some once fired cases from my 5.56 and see how the compare to your 260.

 

[Broz]

I guess you were on the right track all the time then. I just did not think a tight chamber would do that. I have learned someting from you on this one . Glad to hear your bud got his rifle back too. I will go look at some once fired cases from my 5.56 and see how the compare to your 260.

I was thinking the headspace was too tight. But I don't really think they have it completely fixed, by polishing the chamber. For sure the rem's are better. But is that because they are a softer load ?? At first it blew out a primer and really damaged the back of the case. We are going to see what happens. But if this rifle will not shoot some factory ammo, I think it still has a problem.

Please do look at your cases. It would be nice to know if they all do this. I will add, the ejector pin mark in worse than the pic shows. I am just use to not seeing any brass pushed into the hole. If is is, I back off my load.

Thanks, for the help!

Jeff

 

[Broz]

Well, back out to the range with the rifle today. Two kinds of Remington Factory ammo and the origional factory Federal ammo. Here are the pics. It is not much if any better than it was origonally. I don't know what they did with it for 5 weeks. But they sent it back saying it was fixed. I have been involved with this rifle from the start. Barrel has been and still is in proper break in process. It shoots a steller 3 1/2 to 5 inch groups at 100 yards. Look what it is doing to the brass. I am sorry boys, but I have to call this one a $1400 piece of crap. It is for sale!

Any suggestions are welcome.

Jeff