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View Full Version : what, where when how and why would this BCG be used?



ty50
01-08-19, 17:11
The JP ULTRA low mass ALUMINUM BCG.

I'm not at all trying to be a smart ass as I have tons of respect for JP.

I am just curious. I realize the whole adj. gas block/dialing everything in etc. in search of minimal felt recoil.
However, I was surprised to lear a while back that aluminum on aluminum friction can be disastrous at best.
I figure there is some coating on this BCG. But so darn light.

Another reason I am thrown off is that BAD and BENTWOOD designed the OIP sub 4 lb. which I believe is middy gas yet still went with the full auto M16
BCG. Yes in titanium however they worked really hard to get that gun to sub 4 lb. and the BCG, although titanium, is a couple ounces at most lighter than a standard mil-spec weight BCG.

Anyway, if anyone feels like shedding light on that, cool. Thank You

TomMcC
01-08-19, 18:43
It would be used in competition as one of the components to help reduce recoil.

mpom
01-09-19, 19:33
Yes, for competition, but only in conjunction with an adjustable gas block or gas key, as full gas from an unregulated gas block would likely damage the receiver extension end and also would not reduce recoil very much.

TomMcC
01-09-19, 19:40
Yes, for competition, but only in conjunction with an adjustable gas block or gas key, as full gas from an unregulated gas block would likely damage the receiver extension end and also would not reduce recoil very much.

Yes, that is correct. It does no good to lighten the BCG without regulating the gas supply. Also, aluminum carriers wear out considerably faster.

BWT
01-09-19, 20:02
Less mass, less inertia, and less recoil.

Reliability suffers, but that’s just like all extremes of performance.

God Bless,

Brandon

MistWolf
01-09-19, 21:09
Less mass, less inertia, and more recoil
Less mass = more free recoil

BWT
01-10-19, 05:00
Less mass = more free recoil

If the overall system yes, like a lighter weight bolt action has more recoil than a heavier one.

A reciprocating carrier though that unlocks after the bullet has left the barrel and cycles? I wouldn’t think so.

I bet bolt bounce becomes more of an issue as the carrier lightens.

God Bless,

Brandon

MistWolf
01-10-19, 06:03
Reduce the mass of any part of a firearm, even the reciprocating mass, reduces the mass of the whole firearm. Reducing the mass of the firearm increases free recoil. Simple physics.

Changing the reciprocating mass, spring rate etc., can change the attack, sustain and fade of the recoil, which is described as felt recoil.

MegademiC
01-10-19, 07:42
Reduce the mass of any part of a firearm, even the reciprocating mass, reduces the mass of the whole firearm. Reducing the mass of the firearm increases free recoil. Simple physics.

Changing the reciprocating mass, spring rate etc., can change the attack, sustain and fade of the recoil, which is described as felt recoil.

To add:
You are reducing the overall mass by a very small% but the reciprocating mass by a large %.
This will lower the force of the impact of the buffer hitting the back of the RE. Lower peak, lower felt recoil as its distributed more evenly over the time it takes to cycle.

MistWolf
01-10-19, 08:48
To add:
You are reducing the overall mass by a very small% but the reciprocating mass by a large %.
This will lower the force of the impact of the buffer hitting the back of the RE. Lower peak, lower felt recoil as its distributed more evenly over the time it takes to cycle.

Yes. It can make changes the attack, sustain and fade of the felt recoil

TomMcC
01-10-19, 12:44
Usually the guys using an aluminum carrier are going for a certain feel in their rifle...less "felt" recoil and a flatter muzzle rise. They are also using a lighter buffer, an adjustable gas block, a really good brake, a tuned spring, and maybe rifle gas and adjustments in the weight of the rifle. It's a package deal.

markm
01-10-19, 13:46
as I have tons of respect for JP.

Why? I wouldn't buy a single thing they sell.

TomMcC
01-10-19, 13:54
They have a good rep in the competitive world.

kirkland
01-13-19, 21:38
Ar you guys seriously talking about recoil in a .223 rifle? Shoot a .308 and get back to me.

ty50
01-14-19, 02:03
I appreciate the replies. I’ve been MIA for a few days. Checked replies and appreciate them. I’m no novice but far from an expert and there’s always more to learn. It just kind of made me curious that a BCG that weighs so little is of interest to anyone. The competition class makes sense but I would think that a low mass carrier ~7-8oz. would suffice and anything lighter, especially at that premium price, would never make it to anyone’s parts list for a build.
That’s all. Oh and Markm, I guess “tons of respect” is overkill but respect? Sure. They have come up with some good ideas.
Their buffer spring is virtually ingenious. Despite the fact it won’t work for everyone. Pls don’t take that wrong, just sayin.