Why Does my AR not cycle?!? [Archive] - Glock Talk


View Full Version : Why Does my AR not cycle?!?

01-02-2011, 09:56
Hi all,

I have a DTI-15 from Del ton Inc, and am having some major troubles with it. When I first tried to take it out to shoot, it would not even strip the first round off the magazine and send it to the chamber all the way. It would end up half way in, or almost in but the bolt would not seat properly, with no effect from the forward assist. So I was thinking maybe a weak buffer spring at this point. But before I made any mods to it I took it to a local (northwest florida) gunsmith, who proceeded to cycle a whole magazine worth with the charging handle. His advice was basically to "not be gentle with it". This made sense as it is a mil spec rifle. I then took it home and cycled another magazines worth of rounds through it.

Ok so fast forward to my next range visit. The first round enters the chamber fine, and I would then get a max of probably 5 rounds through the gun before a jam. The majority of jams are the round just not entering the chamber fully. Once I ejected the stuck round, I found them to be bent and scratched up, with the bullet actually able to be removed from the casing on a few of them. Ok so my next thought is bad magazine. I then proceeded to borrow two mags from another shooter at the range, 1 armalite 10 rounder, and a 30 rounder that I'm not sure what the brand was. The person who lent them to me said the 30 rounder had a special follower on it so it should be real effective. The armalite ran about 3 mags through before a hangup, and his other mag was about 50 percent effective.

So I am kind of at a lost with all this. Now keep in mind I have not changed anything yet. I may switch buffer springs for the next trip to see. But with 4 different magazines (PMAG, Armalite, a generic 30 rounder, and the mag with the special follower) I am not getting anything consistent from the gun. The rounds are PMC bronze fyi. I am going to run it by the gunsmith again but in the mean time, what do you all think. At this point my best guess is maybe a bad feed ramp, but this problem may be getting over my head. So any help is greatly appreciated. Thanks in advance and take care.


01-02-2011, 10:18
Disregard, missed it.

01-02-2011, 10:21
Call Del Ton.

01-02-2011, 10:33
Call Del Ton.

Yep they will take care of it.

01-02-2011, 10:34

Field strip the rifle, spray generously on bolt, carrier and upper receiver where the bolt rides.

This will help with breaking the rifle in.


01-02-2011, 10:38
What weight buffer? What length barrel? What size gas port? Does it have M4 cut feed ramps?

01-02-2011, 12:15
A propperly built rifle does not need a break in. If your rifleis lubed properly and if you can discount the mags as being the issue there are still numerous reasons for the problem. As asked above more info is needed and even then it may be hard to diagnose over the net.

01-02-2011, 12:20
Lube. You can't start running dry rifles until surfaces have mated.

01-02-2011, 12:38
I bet the bolt carrier is getting hung up on the painted surface of the upper receiver.

01-02-2011, 13:14
I think you probably need to find someone that knows how to run an AR 15 and give you good advice. Without seeing the weapon, I can't tell you what is going on, but Del Tons usually run pretty good. Sounds like it is just dry. The bolt and carrier need to be wet to run good. If they are dry, it will do exactly what you are describing.

01-02-2011, 13:25
Along with the other stuff people are recommending to lubricate, I would try lubing the buffer and buffer spring. Unless you are in very dusty conditions it's recommended to do this. Also it will help with that "BOINGGG" sound you might be hearing every time you fire.
I'd try CLP first or maybe even automotive moly chassis grease. No need to slather it on just put a light coat at first and see what happens.

01-02-2011, 14:29
I would try lubing the buffer and buffer spring.

What is that going to do?

Unless you are in very dusty conditions it's recommended to do this.

Who recommends doing this and the reason ?

Also it will help with that "BOINGGG" sound you might be hearing every time you fire.


OP, find someone close to you that knows WTF is going on with an AR15 and have them look at it.

01-02-2011, 14:38
I'm tired, and my brain is fried today, but possible issue with a carbine rifle, and not having carbine feed ramps?

If the bullet is getting jammed on the feed ramp, its either a messed up ramp, bad magazine spring, or buffer spring in my mind.

You eliminated the possibility of mags, so I'm going to go with buffer spring since it didn't happen reliably with the other mags.

01-02-2011, 16:19
MVI, you may be surprised at how many short stroking issues can be cured by lubing the buffer/spring/rec. ext.

01-02-2011, 16:28
Lube it up till the bolt and carrier drip, and try again. Sounds tight/dry. I dry cycle my new builds about 100+ times lubed up a bunch before I try any ammo. Then, I only load 1 or 2 rounds in a mag for a few rounds till I am sure that the function test was right and the rifle will not double.

Gunnut 45/454
01-02-2011, 20:11
Yep sounds like a lube problem! Did you strip it down and clean it before you tried to shoot it? Always strip a new rifle down and clean the factory lube /grease out before shooting them! And yes you need to lube the buffer spring !:whistling: Also get yourself some full powered ammo-5.56mm unless you have a .223 Rem chamber! Shoot a couple hundreds rounds through it!