User Panel
I'll tell you my RRA is staked much better than my Bushmaster.
|
|
Well, after reading this thread I decided to stake one of my carriers the way Tweak demostrated and I think I fucked it up. I used a screw driver... is that bad?
Oh well, I will shoot the hell out of it minata and see if it comes loose. It really looks bad but it might work fine. |
|
Get a punch, they are built for it. |
|
|
I started a mirror in Troubleshooting.
It should keeep the screws from loosening, but more importantly it keeps the heads of the screws inside the key if the heads snap off. You ain't had fun until you've dealt with that.
Anything that saves me having to type doesn't suck
Put a couple drops of oil on top of the carrier and slide the key across it's mating surface until it stops dragging. Usually the mouths of the screw holes have burrs on them as well as being raised slightly above horizontal. There are often matching burrs on the underside of the key. Better gas seal and a cleaner mating surface so the key won't come loose once the screws are tightened and shot. Once your key is staked go out and shoot a couple dozen rounds through the rifle and RECHECK that your screws are tight. |
||||
|
this is the pic most folks come up with That is field replacement staking, good enough to get a rifle back on the line but not factory correct. How to stake carrier key bolts |
|
Ah, ok... got it. |
|
|
it is still better than the method I showed at the top of the page, as long as the key is displaced into the head of the screw.
|
|
OK, I'm starting to get a bit confused here... I have two carriers, like the top and bottom - just not as deeply staked. Are they both considered acceptable? So far, so good with either, but y'all are makin' me nervous! I think I'll try to stake each one a bit deeper and see how each holds... Given a choice between the two, which is THE preferred?? |
|
|
It appears to me that someone took a file and made a slash across the key to make it "look" like it was staked. It also appears that the maker decided his bolts should say "MP" and pulled out the engraver. |
|
|
I may be asking a stupid question but oh well.
Why dont manufactures just make the key part of the BC? |
|
Ive found that the diamond point chisel from the cheapy harbor freight set works best for staking carriers and castle nuts. IMHO staking works better on castle nuts because its prevents the nut AND extention turning together in the receiver threads against the endplate, since the endplate is held in place by its own little locator.
|
|
I doubt MP stands for Magnetic particle Proof load in this case as only bolts and barrels are test fired, carriers are not.
As long as key material is displaced into the screw heads they should stay tight as long as the screws were tight to begin with. Keys wear and more often get bent, especially when dropped. Cheaper to bolt on a key and replace it when necessary than replacing a carrier with key attached. Of course the original design didn't have a key on top so that may have also influenced the design. |
|
I was talking about this photo where the bolt is MP marked (the middle one)...it looks like one of the CMT Bolt/Carrier that Denny/GTS sells, no? I never said the carrier was MP tested or marked.
http://i2.photobucket.com/albums/y41/boltcatch/carriers.jpg |
|
ah, I thought someone had seen MP marked key screws (bolts) and that is what I meant. I have seen screws marked MP. |
|
|
sevensixtwo, I was referring to Tweaks above mentioned comment...not yours.
|
|
8 Colt carriers, no problems.
1 CMT carrier from Noveske, came loose after 200 rounds. John asked for it back, sent me a new one properly staked. The bad one was barely finger tight. |
|
I staked a CMT carrier for a friend that was exactly like in the first picture in this thread.
I had to hammer the hex wrench into the bolt head because they had deformed it. From the alignment marks after tightening the bolts to where they were originally when staking was factory attempted, they were about finger tight as Tweak stated. CMT makes excellent product for the money but they really need to invest in proper tooling/training for carrier key staking. My advice for vendors would be to check these and fix them in house before they ship them out, it will cut back on the future RMA's and will proabally net them less work. Also for them to lean on CMT to fix it at the source. |
|
|
||
|
Great thread. I am loosing my conficence in the CMT bolt carriers. I took a look at mine and was able to loosen the bolts very easily. I have since used RED loctite and restaked it. It looks like CMT may be cutting corners here.
DT |
|
Good luck ever replacing the key without snapping the bolt heads off. Make sure you don't ever drop it on something hard as the key is proabally the most easily damaged working part of the rifle. |
|
|
|
Last night I reprofiled the end of a 5/32 punch and re-staked my brand new CMT BC. I used a dead blow and hit it three times on top as pictured on page 3. Looks a lot more secure with 5 stakes in it. Before re-staking I tried tightening the bolts and they weren't budging.
The above pic looks like it has a better stake job that mine did...much deeper. |
|
Musta benn a STAG! I had to restake a few myself! The dealers on this board should put a fire under CMT/STAG & tell them to do the job properly, not half assed!
|
|
not unsafe, just prone to loosening and incorrect. |
|
|
I think I'll check all mine when I get home.
Thanks for the heads up. |
|
Doing things right the first time tends to net less work in most things |
|
|
I have sold a few hundred CMT/Stag bolt carriers and Bolt carrier groups and I have had NO feed back from even 1 purchaser of a key or carrier key bolt coming loose. If I had had a complaint or especially numerous problems stemming from their staking method it would have been addressed immediately. In the absence of any feedback from purchasers it is pretty hard to know there is a problem in any area. Or perhaps there is no problem, just panic in the streets. I have built many, many bunches of bolt groups from scratch over the last 25 years working on these black rifles. I use the field method illustrated by Mongo in the post above and never had a failure. As long as an adequate amount of key material contacts the screw this method is just as effective as the "factory" method. I have examined hundreds of Colt C marked carriers. A great number of the were staked from the factory with the Mongo example of staking. We are talking M16's here and all were fine. If you have concerns about your key screws, run over them with an allen wrench and the stake as illustrated with the field method, it works just fine. Denny PS Checking the screws every once in a while is just normal maintainence at our place. |
||
|
Contrary to popular belief here at Arfcom, cheaper typically means corners are being cut somewhere. |
|
|
Or perhaps marked it like the bottom bolt, which is from Fulton Armory. As I said in my initial post, that one in the middle is a CMT M16 BCG. It is advertised as MP inspected, and marked as such by them. I got it from another arfcom vendor, not GTS, but it is the same item. Someone else said it looked like file marks, but it is definitely a "staking" done with a long flat sharp edge, one strike across each screw. I really didn't set out to get the MP, it's just that I wanted the M16 carrier and it was only offered with the MP, as opposed to the semi BCG's which are offered in MP and non-MP. Someone correct me if I'm wrong, but it was my understanding that bolts from, say, Colt, are (like the barrels) proof fired and then mag particle inspected. I assumed that the CMT MP bolts were just mag particle inspected, which I wouldn't really expect to mean much. |
|
|
I just use a torch or soldering iron lightly to break the loctite. I really do not have a lot of confidence anyway that the red loctite will hold as the BC probably gets hot enough to degrade it. |
||
|
If you are going to be useing Loctite in a high temp area where the bolts/screws are 3/4 or less in diameter then you should use a high temp Loctite like #266. |
|||
|
I have a product called "Rockset". It is a 1200 degree cement. I use it to secure suppressor mounts like Gemtech Bi-Locks, Troy's, Surefires etc. It is the same material that Gemtech used to supply with their cans. I got the 411 on the product from Phil Dater. This might add some extra insurance on carrier key screws. Stuff is relatively cheap at $15 for 2oz. I have done a lot of suppressor mounts over the last 2 years and still have over half of the original bottle left. Denny Oh yeah, good luck getting it loose |
||||
|
It could also mean paying more for the Colt name only. I have seen every brand name AR bashed here on ARF, every one. Let's just get over it. Buy what you want. No need to bash the other guy. If you buy a part or an entire weapon here on ARF and it truly has a problem, not an imagined one or what you percieve to be a future one, the dealers here will take care of you. Some time ago I saw a thread here where a guy was just ranting because he got a bad bolt hold open, jeeze, just call the dealer. He will send you a new one and you can spend 10 minutes to replace the broke one. It doesn't deserve 6 pages of bashing the mfg. Some things you just fix and move on. Think of it as learning how to work on your weapon and proper maintenence. Denny |
||
|
I think the issue arises (carriers in particular) because, unlike other processes, there is
room for interpretation when it comes to staking...so OK, some much better. |
|
Possibly, but if that were really true, would they be teetering on the brink of bankruptcy year after year? |
|
|
it''s not if a manufacturer has problems, it's how often and how severe are those problems. We can track that (like BFIs loose keys and canted barrels) by reporting it. No one should have to work on a new gun, shouldn't even have to inspect it. Anyone detail strip their new car before driving it just in case some hack didn't tighten the oil pan bolts?
|
|
I agree with you totally Tweak. The board is a very useful resource for tracking chronic problems with any and all manufacturers. This board and its members have solved or had improved many weak areas in some manufacturers products. Anecdotal (SP?) complaints without pics I discount. Too much "I heard from a buddy that his father-in-laws friend had such and such." Useless bashing with out pics. Denny |
|
|
With the hundred of millions of $$$$$$ Colt drags in each year from .gov and .mil contracts I honestly see how they have so many financial crisis'. Could it just be poor financial management. For the life of me it just amazes me. Also ignoring the civvie market. STUPID, STUPID. If Colt made their police type ARs available in quantity to the general shooting public they would own the market in a year or two, given reasonalble prices. I love Colts, but they make it hard. As to money they just bought Diemaco in Canada??????? How does an insolvent company pull that off. They also tried to buy H&K at one time. Colt's finances are a puzzle palace to me. Maybe someone can explain it to me. I would like the inside scoop. Denny |
||
|
Looks like I'll be staking the key on a new Stag Arms upper I just recieved yesterday. It has the thin shallow mark across the screws like the middle group pictured (CMT). Thanks for the thread Tweak, good timing for me as I'll be breaking this thing in tomorow.
|
|
Make sure they actually are tight and not just hand tight before you apply the stakings.
|
|
Yup. FWIW, the manual states the hex screws should be tightened to 35 to 40 Inch-pounds (3 95 to 4 52 N m). (I have been reading the manual lately- anticipating my middy build) |
|
|
That number is hideously low, no doubt to keep thick headed armorers from shearing off screw heads. Take them down tight then a smidge more. |
|
|
Sign up for the ARFCOM weekly newsletter and be entered to win a free ARFCOM membership. One new winner* is announced every week!
You will receive an email every Friday morning featuring the latest chatter from the hottest topics, breaking news surrounding legislation, as well as exclusive deals only available to ARFCOM email subscribers.
AR15.COM is the world's largest firearm community and is a gathering place for firearm enthusiasts of all types.
From hunters and military members, to competition shooters and general firearm enthusiasts, we welcome anyone who values and respects the way of the firearm.
Subscribe to our monthly Newsletter to receive firearm news, product discounts from your favorite Industry Partners, and more.
Copyright © 1996-2024 AR15.COM LLC. All Rights Reserved.
Any use of this content without express written consent is prohibited.
AR15.Com reserves the right to overwrite or replace any affiliate, commercial, or monetizable links, posted by users, with our own.