Do I Need An Extra Bolt Carrier?

[madcratebuilder]

I have wondered about this big time for about a year. I have a basically brand new Bushmaster AR srt ip as a CQB carbine. It's a present for myself for surviving major back surgery last Oct and I finished it's customization last December. Had the gunsmith finish some stuff and then also go over the rifle making sure it was all good and ready to rock s d roll and once-overed. He said it was great n

The thing is ppl recommended the new BCG. I would like to get a new one ( and better one ) but there are $99 johs all the way to $500 - I want a real good one but not a $500 one. And then I'll have a Brand New Bushmaster BCG for backup. So what should I get ?
Also I want a heav buffer bit do I need any info?

Some ppl say Bushmasters are " Overgasses" so won't a Heavu Buffer help ? Also can I get as heavy as I want or is there' a method ? I see Heavy , H1, H2 , H3 , tungsten z, super duper carbide diamond heavy etc.

Can I Just buy the super heavy one and be done )?

Tytyty.

Several suppliers have complete BCG that meet mil-spec and sell for well under $150.

This is a quality bolt and affordable.
http://www.rainierarms.com/?page=shop/detail&product_id=2012

The Bushmaster M4geries I have owned and worked on seemed to like a H buffer with a oem spring or a CS moly coated spring. The moly coated springs help reduce the "spooong" noise from the RE when firing.

A standard buffer(3.0oz) is unmarked, then you have the "H"(3.8oz), "H2"(4.6oz) and "H3"(5.4oz) buffers. There are other heavy buffers that do not follow this marking scheme.

Heavybuffers.com has very nice custom buffers, Slash has been making these for several years now and is the go to guy for buffer/spring requirements.

 

[tAKticool]

Just FYI- I had my gunsmith who is a qunique character- Army Infantry and Ranger qualified - then became a cop, SWAT team member, SWAT assaulter and SWAT sniper, then the SWAT and Police dept. armorer .... then became the head instructor for SWAT... and decided finally to become a full time career gunsmith and after doing all the schooling formality and certifications, sept 11 happened so he joined a private security company and went to Stan, Iraq, and then Stan again.. he not onlychecked out and worked on my Bushmaster I asked him to pay specific attention to the BCG.

He said a LOT of the guys in his 'merc' company used Bushmasters. He had a real neat personal carbine, it ewas an old Colt M16A1 receiver with full auto, but it had a real small compact fixed stock, and then it was an M4 build forward....a short 14.5" bbl, 7" LaRue free floating quad rail, and a sweet C-More Tactical holodot sight on top. He said that the guys in the company who could not get full auto AR's etc. for deployment, they were taking brand new Bushmasters right off the shelfs of gun shops, dfoing all their personal mods, and shoting them. He said ppl loved Bushmasters and they were considered great brands (Like Colt was consirdeed of course the best).

He also said, my BCG was fine, the gas key was not super duper staked but it was 'acceptably' staked and he made a great comment- he has been following allong the net critizsm of both bushmaster and their gas keys in specifics- and he said, look, what is the problem here.. they set a 'mnimum' to have to set 'staked" at, they do that, and now its not good enough, it needs to be super staked AND loc tited.... well if THAT was necessary why dont we all change the minimum to THAT new super process? At some point its just like the shaver things.. well 3 Razor bldes was agreat idea,. Now I'll go FOUR BLASDES!!!

well now I'll go FIVE blades!!! and not only does your 4 razor blade suck, the 3 razor blade that I used to buy and love, IT SUCKS NOW TOO. and it sucks even tho I used it for years.

 

[moxie]

There's nothing wrong with motor oil as gun oil. In fact it works nicely, as does plain old grease.

Go to the auto parts store and buy a quart of Mobil 1 5W-20 and a tub of Mobil 1 grease. Together they will cost less than $15. This combo will keep ALL your guns running sweetly for many years!

 

[Bartholomew Roberts]

He also said, my BCG was fine, the gas key was not super duper staked but it was 'acceptably' staked and he made a great comment- he has been following allong the net critizsm of both bushmaster and their gas keys in specifics- and he said, look, what is the problem here.. they set a 'mnimum' to have to set 'staked" at, they do that, and now its not good enough, it needs to be super staked AND loc tited.

The issue with Bushmaster is that at one point they relied on "chisel" staking where they make a line across the top of the screws with a chisel-type tool. This type of staking is usually adequate if all of the other parts of the procedure (torque, proper grade fasteners) are done correctly; but it is not the way the military requires gas keys to be staked.

Around 2005, Bushmaster had a major quality control issue with a machine where they did not set up the machine properly and hundreds, if not thousands, of bolt carrier groups left with loose keys. This cause widespread problems for them; both in agency purchases and civilian purchases.

Since around 2009 or so, every Bushmaster I've seen is now staked according to the military method. I have no idea what your gunsmith is talking about; but now you know how Bushmaster got that reputation.

 

[madcratebuilder]

This is from the ARMY TM 9-1005-319-23&P.

NOTE
Do not retorque carrier and key screws if staking marks do not indicate loosening screws.
Repair by replacing, torquing, and restaking carrier and key screws. Refer to the following reassembly procedures
NOTE
Do not reuse old carrier and key screws
New carrier and key screws must be
used at assembly.
Use a tight-fitting 1 8 inch socket head screw
wrench attachment and an Inch-pound torque
wrench to torque the carrier and key screws (3) to
35 to 40 Inch-pounds (3 95 to 4 52 N m)

4. Use solid center punch and hand hammer to
stake the two carrier and key screws (3) In three
places.

The following is in several places in the 23&P.

NOTE
Do not retorque carrier and key screws if staking marks do not indicate loosening screws.
Repair by replacing, torquing, and restaking carrier and key screws. Refer to the following reassembly procedures

Looking at the Armies method of staking it's not intended to capture the screw but to have a visual indication that the screw may becoming loose. This type of staking has been used in military rifles for the past 150 years. Mausers and Enfields have several screws staked.

The above staking procedure is for field units and does not represent how a manufacturer well stake the key screws.

Young manufacturing makes one of the best BCG's you can buy. They are not staked and if you do stake the key it voids the life time warranty.

I have a older Colt FA BCG and it is very lightly staked in two positions. As far as I can tell the key is original, I've used this bcg for twenty years or so, screws are still tight.

 

[Bartholomew Roberts]

Looking at the Armies method of staking it's not intended to capture the screw but to have a visual indication that the screw may becoming loose.

This is not correct. The whole point of staking is to impinge some of the metal of the key onto the screw to limit its rotation. If the only purpose of staking was to provide a visual indicator, you wouldn't need a complicated process to stake it in three separate place, you'd just draw a line across the top of the screws with a paint pen to make a witness mark.

Young manufacturing makes one of the best BCG's you can buy. They are not staked and if you do stake the key it voids the life time warranty.

Young doesn't stake because they use Permatex Thread Locker instead of staking - which considering their main product is hard-chromed bolt carrier groups, makes a lot of sense. And as they point out on their website, the problem is not with staked gas keys; but rather improperly staked gas keys in which people go to extremes and actually stake the gas key so aggressively it stretches the threads on the screw (or alternatively people don't use the correct fasteners and torque to the proper amount (56 inch-pounds) which leads to a screw that is either more fragile, under-torqued, or over-torqued; but is now staked in place.

Proper staking should not make it impossible or even especially difficult to remove the screws on the carrier key.

 

[madcratebuilder]

Quote:
Looking at the Armies method of staking it's not intended to capture the screw but to have a visual indication that the screw may becoming loose.

This is not correct. The whole point of staking is to impinge some of the metal of the key onto the screw to limit its rotation. If the only purpose of staking was to provide a visual indicator, you wouldn't need a complicated process to stake it in three separate place, you'd just draw a line across the top of the screws with a paint pen to make a witness mark.

Read the 23&P. The Army method does "capture" the screw but not nearly to the extent we see with most current production carrier keys.