Finally Test Fired my Del-Ton 16" Lightweight....and serious problems emerged

[pastfinder]

Well, after not being able to get out to shoot my Ar-15, I finally hit the backwoods today to test fire her. I was shooting PMC .223 55grn FMJ brass cased ammunition out of standard GI 30 round magazines with MagPul no tilt followers and Thermold 20 round magazines.

For the first shots I loaded up a 30 round mag. It did not want to load and lock into place without a good smack on the bottom. Once seated, it was fine, and the magazines ejected without issue (nice smooth release). These first 30 shots went off without a hitch, clean trigger pull, smooth cycling.

I set the rifle down after firing and let it cool. Next, I loaded one of the 20 round Thermold magazines. It too required some umph to lock into place. I chambered a round and fired without issue. I fired again and here the problem emerged. The spent casing was not ejecting, and a live round was being stripped and together they locked into place. After ejecting the magazine, I cleared the jam, the shell casing and live round fell out of the magazine well, and I reinserted the magazine and chambered another round. The first shot when fine, then the second one jammed up again with a stovepipe/double feed. In some cases, the spent casing jammed so badly as to require me to use needlenose pliers (going through the mag well) to pull out the mangled casing. Mangled is the opportune word here, as this brass is good now for little more than being turned into scrap.

I switched from the Thermold mag to the GI mag but the exact same occurrence happened. First shot = fine. Second shot = double feed jam. Also, after just trying single shots (loading one bullet into chamber without a magazine), the rifle would not eject the spent casing. If you manually cycled the bolt it would eject.

I cleaned the rifle and the gas tube prior to firing. I'll call Del-Ton on Monday and explain this, as well as email them this description. I'm more saddened than angry at what happened. Just want my Ar-15 to work is all.

My cell phone camera took this photo of one of the jams. The casing is wedged above the bolt and the end of the charging handle.

[308]

Those pig-piles are nasty. I assume you know how to clear that jam effectively?
Every time I've had that sort of thing happen was due to crappy ammo.

[imanaknut]

Was going to say something about the ammo too. Suggest another thorough cleaning, and then try a different brand of ammo. I had one AR that simply would not work with one brand, but never had a problem with anything else.

Also, you mention that you really have to slap the mag to get it to lock. Are you inserting it with the bolt locked back, or forward?

[deth502]

first thing id do before anything would be to completly field strip it and make sure everything is assembled correctly. especially check the extractor and ejector. use a punch to push the ejector and extractor back and forth through their normal operating range and make sure there is no binding, roughness, or excessive play in any of the parts.

id even go as far as to say, for a simple fix, swap out the bolt from another ar, if you have one available, and see if it works any better. just as a process of elimination.

[Schuetzenman]

This a 16" barrel right? Does the extractor have the black rubber O-ring under it to increase extractor power? As mentioned it could be the ammo from the perspective that the recoil stroke isn't going back far enough to completely eject the spent case, but it goes back far enough to strip another round and create that kind of jam.

Has the bolt carrier got any lube on it, and how about the buffer tube? Is there any lube on the buffer spring?

The having to smack the mag good to get it to seat when full is typical. You can avoid that by simply having the bolt locked back when you insert the mag. Then it will go in easy as pie. After locked in, give the bolt release a punch and the bolt will drop and strip a round into the chamber.

You are discovering what anybody that owns an AR eventually learns. They aren't as inherantly easy to get to work as the trusty AK type weapon. But in time you learn how to deal with the issues and get reliable function with much better accuracy than any AK can deliver.

[pastfinder]

Hi All,

Thanks for the reply. I cleared that jam (and others) with a pair of pliers to gently pull the case out of the way and allow the bolt seat properly.

I will try different ammo. Perhaps Remington or something at the store. Pricey but hopefully that will work.

This is a 16" rifle and I cleaned it thoroughly before firing it. There is no black o-ring on the extractor. I had some lube on the bolt carrier rails, none on the buffer tube or buffer spring.

The only "damage" I can see is that the charging handle has some nicks/dings from the shell casings slamming into it. Other than that the bolt carrier and bolt show no damage of any sort.

I'll still call Del-Ton to see if something may be an issue or if they have advice. If at nothing else, they are literally a two hour drive from my summer home, so I could drive down there and get their reactions first hand. Tis annoying...at least my Ak can eat garbage without missing a tick.

[pastfinder]

Sitting down to clean the rifle thoroughly tonight. Hopefully I won't find any other surprises.

[kimberkid]

As already pointed out; it sounds like its short stroking, carrier not going back far enough to eject, but far enough to strip the next round out of the mag.

Also pointed out the common culprits: weak ammo and/or lack of lube on carrier or buffer / spring

Also check your gas key ... sounds like it may have not been staked properly and has worked loose, it doesn't have to be very loose to cause a problem.

[pastfinder]

I read not to oil the spring or buffer, so I have put nothing on them at all. I oil the sides of the bolt and the rails of the bolt carrier, but that is all. After cleaning, the only major grime I found was on the bolt (as usual). Nothing, aside from the charging handle mentioned above, shows signs of the jamming or abnormality.

I'll grab some different ammo and try that out. Should I lube the buffer spring and tube lightly with CLP?

[FunkyPertwee]

I read not to oil the spring or buffer, so I have put nothing on them at all. I oil the sides of the bolt and the rails of the bolt carrier, but that is all. After cleaning, the only major grime I found was on the bolt (as usual). Nothing, aside from the charging handle mentioned above, shows signs of the jamming or abnormality.

I'll grab some different ammo and try that out. Should I lube the buffer spring and tube lightly with CLP?

I don't know much about ARs, but a lot of guns need grease instead of oil.

[pastfinder]

I owned an AR-15 before (Stag) and it worked fine with CLP and cleaning. I've used CLP on my other weapons and never had issues like this Del-Ton Ar.

[Schuetzenman]

Yeah sure CLP is fine enough to lube the buffer spring. It stays fluid even at ultra low temperatures. Do you have any M855 62 gr. ball ammo to try. 16" barrels are easily over gassed and usually they have extraction problems vs. short stroking. Believe me it is easier to deal with short stroking vs. tearing rims off due to excess gas pressure in the chamber at bolt unlock and extract.

I mentioned this in my last post and it probably won't have any bearing on fixing your current problem. I am including the link for you as a just in case thing. You may want to book mark them.
http://www.brownells.com/.aspx/cid=0...tractor_O-ring

http://www.brownells.com/1/1/18711-a...pak-wolff.html

[pastfinder]

I was going to get some white lithium grease today to put on the carrier rails, and a higher grain ammunition to see if that helps. Thanks for the links Schuetz. Before firing the rifle again I think I'll call Del-Ton to just describe the issue and see what they recommend. I don't want to necessarily experiment and damage something irreparably.

[308]

I cleared that jam (and others) with a pair of pliers to gently pull the case out of the way and allow the bolt seat properly.

In the future, or if/when pliers are not around, and/or your life depends on clearing that round, do the following:

1. Remove the magazine
2. While keeping a rearward pull on the charging handle, strike the butt stock hard on a hard surface. The rearward momentum will force the bolt carrier backwards and spit the empty case out.
3. I call this the semi-auto Heimlich Maneuver
4. Works well for the M1A also
5. Keep things pointed in a safe direction of course...

[Schuetzenman]

I was going to get some white lithium grease today to put on the carrier rails, and a higher grain ammunition to see if that helps. Thanks for the links Schuetz. Before firing the rifle again I think I'll call Del-Ton to just describe the issue and see what they recommend. I don't want to necessarily experiment and damage something irreparably.

Your plan for heavier bullet is the easiest way to check if it's a lack of gas pressure. On my 16" middy that I converted to piston drive, it was doing the same thing in the beginning. I had the ACE Socom Long stock which has a full length rifle buffer tube size vs. a carbine buffer tube size. So I put a rifle buffer and spring in it. Because of that it would not reliably function with anything less than my 69 / 68 gr. hand loads. 55 gr. M193 and 62 gr. M855 mil spec. ammo wouldn't eject or would do what you have shown. I purchased a carbine spring and buffer and put those in. The next trip to the range it would run anything from 55 gr. up. I assume it is a standard Caribine length gas system 16" not a midlength.

On the lithium grease, I've used it, it does work. Just be careful to not get it too thick. The layer you lay down should be very thin, see through in nature. I will say that the lithium will combine with the carbon that blows back into these DI guns and makes a very black paste that thickens as more carbon is introduced. In some ways I think CLP does a better job of keeping the carbon loose and fluid. I have restored function to AR rifles that would not fully go into battery by simply dropping some CLP on the Carrier thorugh the Ejector Port and then hand cycling the weapon, (with the mag out) to distribute the CLP. Put mag back in and off she ran for the rest of the range time.

[Schuetzenman]

In the future, or if/when pliers are not around, and/or your life depends on clearing that round, do the following:

1. Remove the magazine
2. While keeping a rearward pull on the charging handle, strike the butt stock hard on a hard surface. The rearward momentum will force the bolt carrier backwards and spit the empty case out.
3. I call this the semi-auto Heimlich Maneuver
4. Works well for the M1A also
5. Keep things pointed in a safe direction of course...

Good post, I do that too for clearing such a jam. Another technique is to use a range roof support post to help clear the stuck bolt carrier. Works best if the posts are square. With the weapon unloaded, put the charging handle latch up against the edge of the post then smack the buttplate with the heal of your hand to drive the weapon forward. This will aslo unstick a stuck carrier.

[5.56NATO]

When you have to slap the mag in place I am guessing the mag is not milspec. Far worse if your lower is.

[pastfinder]

Thanks for all the good info. I just opted to CLP the bolt carrier rails. I've used (and this sounds insane) Penn fishing reel grease for rails before and it works fine without running or trapping too much carbon gas residue. I clean my weapons after every shoot and if in storage for a while I opt for grease and heavier oil. This gets cleaned off before shooting and I just use a little CLP.

I'm calling Del-Ton tomorrow (I emailed them) and seeing if I should just get some mil-spec ammo and try that out. Otherwise I'll just make the 2 hour drive to Del-Ton and bring them the rifle to test/repair.

[Schuetzenman]

When you have to slap the mag in place I am guessing the mag is not milspec. Far worse if your lower is.

I guess every one of my M16 / AR15 mags aren't milspec then right down to the ones with the contract number on them. They all require a hard smack to seat if fully loaded and the bolt is forward. To eliminate the effort I simply pull on the charging handle and lock the bolt group back for mag insertion the first time. Ever there after the bolt is locked back by the follower so it's ready for a full mag with no slapping involved.

[308]

I suppose one other thing to consider is a misaligned FSB/Gas port. That would lead to some short stroking as well. Just another $0.02 thought