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ROUGH
08-25-06, 12:39
I just wanted to start off by saying WOW an actual technical discussion board with out :mad: matches happening every 10 posts, I look forward to accessing and using the knowledge here that is based on fact from real users and not opinion.

Excellent forum thanks for starting it. ;)

Ok for my first post I have a question about Buffer / Bolt Carrier Weight Combinations. The M16 with a non-collapsible stock has a rifle length buffer and an M16 bolt carrier, as far as I can tell this is the heaviest combination for the combat rifle.

M16 carrier weight = Unknown to me as I don’t have a scale or M16 carrier
Rifle Buffer Weight = 5.15 oz according to http://www.biggerhammer.net/ar15/buffers/

Enhanced Carrier weight = Unknown to me as I don’t have a scale, but less than M16 Weight, because of the milled off M16 sear trip area
9MM Buffer weight = 5.47 oz according to http://www.biggerhammer.net/ar15/buffers/

If I knew the weight of the Carrier’s I could get totals of moving mass, but I can’t seem to find Carrier weights.

Now with the difference of weight between the buffers being .32 oz, I wonder if the difference in weight of the two carriers is close to .32oz. If it is that would
mean a carbine with an A2 stock and rifle buffer system would have roughly the same moving mass, and recoil energy of the Enhanced Carrier with the 9MM
buffer. Not taking into account the difference in weight of the of the rifles with the different stocks.

The reason I bring this up is I have an Enhanced Carrier in my rifle with a 9MM buffer and love it. I used to have an A2 stock on that carbine and between the two I can’t really tell the difference in recoil, other than it is a little lighter with the A2 sock as it is heaver than the VLTOR I have now.

What do you think?

We all agree that a heavier buffer in a carbine is a good thing, but if it could equal the weight of the A2 system would that be better?

Boom
08-27-06, 11:07
I need to clean a couple rifles today with both carriers so I will weight them and post here. Great topic BTW.

PE556
08-28-06, 07:18
First of all, not everyone is going to agree that a heavier buffer in a carbine is best. I happen to tend towards heavier is better though.

The other thing that you are taking into account here is the spring coefficient of the rifle and carbine springs. I don’t know what the spring coefficients are or how much they differ, if at all. This will also affect the functioning of the system just as much as carrier carrier/buffer weight. The thing is, you can’t easily alter spring coefficients as easily as the buffer weight. The difference in the two carrier weights is probably only about ¼ oz.

The Colt Sporter Lightweight I have originally came with an A2 stock/rifle buffer. I quickly DX’d that though. It now has an H2 buffer in it, though I have run it with std, H, H2 and 9mm. All seemed to function fine at the time, as I recall.

I think that you are trying to split hairs. They are roughly equivalent in mass, but there are other things that affect the system other than the moving mass.

ROUGH
08-29-06, 09:58
I need to clean a couple rifles today with both carriers so I will weight them and post here. Great topic BTW.

Thank you that would be great



First of all, not everyone is going to agree that a heavier buffer in a carbine is best. I happen to tend towards heavier is better though.

This is true, it is just an assumption, I read some other posts on another board
that talked about lighter carrier and buffer to reduce felt recoill. This is possible,
but I think the wear to the moving parts would be increased.

The other thing that you are taking into account here is the spring coefficient of the rifle and carbine springs. I don’t know what the spring coefficients are or how much they differ, if at all. This will also affect the functioning of the system just as much as carrier carrier/buffer weight. The thing is, you can’t easily alter spring coefficients as easily as the buffer weight. The difference in the two carrier weights is probably only about ¼ oz.

Sorry I didn't even think about that, thanks for the other variable.

The Colt Sporter Lightweight I have originally came with an A2 stock/rifle buffer. I quickly DX’d that though. It now has an H2 buffer in it, though I have run it with std, H, H2 and 9mm. All seemed to function fine at the time, as I recall.

I think that you are trying to split hairs. They are roughly equivalent in mass, but there are other things that affect the system other than the moving mass.

True, but I thought it would be interesting to talk of something that people may
not take in to account very often.




Thanks for the different points of view fellas. ;)

QuietShootr
09-02-06, 10:35
I just wanted to start off by saying WOW an actual technical discussion board with out :mad: matches happening every 10 posts, I look forward to accessing and using the knowledge here that is based on fact from real users and not opinion.

Excellent forum thanks for starting it. ;)

Ok for my first post I have a question about Buffer / Bolt Carrier Weight Combinations. The M16 with a non-collapsible stock has a rifle length buffer and an M16 bolt carrier, as far as I can tell this is the heaviest combination for the combat rifle.

M16 carrier weight = Unknown to me as I don’t have a scale or M16 carrier
Rifle Buffer Weight = 5.15 oz according to http://www.biggerhammer.net/ar15/buffers/

Enhanced Carrier weight = Unknown to me as I don’t have a scale, but less than M16 Weight, because of the milled off M16 sear trip area
9MM Buffer weight = 5.47 oz according to http://www.biggerhammer.net/ar15/buffers/

If I knew the weight of the Carrier’s I could get totals of moving mass, but I can’t seem to find Carrier weights.

Now with the difference of weight between the buffers being .32 oz, I wonder if the difference in weight of the two carriers is close to .32oz. If it is that would
mean a carbine with an A2 stock and rifle buffer system would have roughly the same moving mass, and recoil energy of the Enhanced Carrier with the 9MM
buffer. Not taking into account the difference in weight of the of the rifles with the different stocks.

The reason I bring this up is I have an Enhanced Carrier in my rifle with a 9MM buffer and love it. I used to have an A2 stock on that carbine and between the two I can’t really tell the difference in recoil, other than it is a little lighter with the A2 sock as it is heaver than the VLTOR I have now.

What do you think?

We all agree that a heavier buffer in a carbine is a good thing, but if it could equal the weight of the A2 system would that be better?


I have used M16 carriers with 9mm Colt buffers in three builds so far, and I have about 10,000 rounds through this setup. The only combination I have had trouble with was when I added a Wolff XP recoil spring - then I would get short stroking with .223 pressure loads. I have sort of standardized on Colt 9mm buffers with ISMI chrome-silicon recoil springs, and my guns run great.

I believe(though my guns are not a statistically significant sample) the heaviest buffer/carrier combination that your gun will run with will probably result in longer bolt/extractor life as well as smoother cycling. When I pick up a stock carbine with a standard CAR buffer in it I'm surprised at the WHACK I can feel when it cycles. I can't help but think that less reciprocating mass=earlier bolt unlocking, therefore putting more stress on the bolt's already overstressed(in a carbine) lugs.

YMMV.

TigerStripe
09-03-06, 00:56
I have used M16 carriers with 9mm Colt buffers in three builds so far, and I have about 10,000 rounds through this setup. The only combination I have had trouble with was when I added a Wolff XP recoil spring - then I would get short stroking with .223 pressure loads. I have sort of standardized on Colt 9mm buffers with ISMI chrome-silicon recoil springs, and my guns run great.

I believe(though my guns are not a statistically significant sample) the heaviest buffer/carrier combination that your gun will run with will probably result in longer bolt/extractor life as well as smoother cycling. When I pick up a stock carbine with a standard CAR buffer in it I'm surprised at the WHACK I can feel when it cycles. I can't help but think that less reciprocating mass=earlier bolt unlocking, therefore putting more stress on the bolt's already overstressed(in a carbine) lugs.

YMMV.

While I don't (yet) run an M16 carrier, the 9mm buffer makes a lot difference in muzzle jump, felt recoil, bolt carrier bounce, etc. I don't see how that could do anything other than help the carbine. I've read somewhere on the net where someone said a ligher buffer is needed because all of the weight/mass being transferred so many times would reduce the functional life of the weapon, but I don't believe this to be the case.

TS

QuietShootr
09-03-06, 10:12
I tested my new SBR build yesterday -
http://sniper.rsvs.net/SBRSmall.JPG

Using 300 rounds of Q3131 - pertinent configuration is as follows:

Colt bolt and M16 carrier (McFarland ring, Wolff XP extractor spring, black insert, D-fender)
Colt 9mm buffer
ISMI Chrome-silicon buffer spring
Brownells magazines with Magpul gen 2 followers

Results: NO malfunctions. Bolt locked back on a single round 5 times, and I fired at least 20 rounds in each of the following positions: loosely in one hand, sideways (both sides) and upside down.

Recoil was smooth with no SNAP at the end of the buffer travel, and ejection was vigorous.

Not statistically significant, I know, but I'm feeling pretty good about this particular build. This parts configuration appears to be a winner.