AR15 Buffer System - Pls Educate Me

I am assembling an upper in 224Valkyrie and am just beginning to learn about the AR15 gas system and buffers. LOTS of info/videos on weights and springs etc., but I could find no answers to a few questions.

Why are there 3 or more buffer weights? Why not a single piece? Adjustability would be just as easily done with single pieces, and it would seem that manufacturing cost would be less.

Why, even with the rubber spacers, is there lengthwise free play in the weight movement within the buffer weight tube? Why can you rattle these things? Why not have enough spacers to have a snug fit filling the tube?

While it seems to be universally agreed upon that the use of heavier buffer weights and stronger springs reduces "felt" recoil, does this improve, detract from, or have no real effect on absolute precision - with respect to the effect of gun and muzzle movement caused by recoil before the bullet exits the bore? (Given that cycling and ejection are A-OK.)

Does anyone have any first hand knowledge or experience (besides the online reviews) with the real effect on precision with the use of alternate buffer weight/spring systems like the JP Silent Captured or Armaspec SRS Stealth systems?

Thanks.

Ever use a dead-blow hammer?

Multiple weights with free play reduce bolt bounce. It's basically a dead blow hammer. Not very important in semi auto. REALLY important in full auto.

Weights are either steel or tungsten slugs. You can make 4 different total weights using a combination from all steel to all tungsten using (and stocking) just two parts.

Buffer/spring really shouldn't affect accuracy.

There are two schools of thought on reducing "felt" recoil impulse, bearing in mind 224 Valkyrie or 556 do not have a lot of recoil to begin with.

before I get to the schools of thought on buffer + spring, IMO the essential components: Muzzle brake, adjustable gas block, and good shooting technique. If your muzzle is rising the stock might be rolling on your shoulder. So a lot of "recoil" is shooting technique. Adjustable gas block will let you tune the gas down to where its practically a bolt gun. But you can also tune the gas to optimize accuracy of a handload or add a suppressor. Tuning the gas will reduce wear and tear on the moving parts as well. Someone may be along to say get an SLR adjustable block, and I will concur with that.

A far as accuracy most if not all of the recoil impulse happens after the bullet leaves the barrel. So when we say "reduce recoil impulse" what I mean and what I think other mean when they say "reduce recoil" they usually mean making follow up shots easier.

These three things will definitely do that.

With a good a good adjustable gas block (for example SLR), you can tune the gas. There are quite a number of muzzle brakes (see tests here: https://www.thetruthaboutguns.com/2016/10/jeremy-s/ar-15-muzzle-brake-shootout-3/). A good 3 chamber brake like Precision Armament M4-72 or the Venom Defense 3-chamber will definitely reduce recoil. However it will be LOUD - something like the PWS 556 (see here for test #1: https://www.thetruthaboutguns.com/2014/11/jeremy-s/556-muzzle-device-shootout/) will be in the middle and reduce recoil 50% but not be as bothersome.

Adjustable gas block, good shooting technique, muzzle brake, all of these IMO will let you tune your gun and absolutely reduce recoil and make follow up shots easier. I 100% recommend these three things.



Now as far as buffer/spring, there are two schools of thought:
1: light buffer and spring like JP Silent Capture, and a skeletonized ultra light BCG, like the Faxon light BCG or JP low mass bolt carrier. I have seen some guys run with this at 3-gun and have fondled and shot their set up.

2. Heavy buffer and spring. This is me right now.

Physics will tell you #2 is the way to go (increase weight), but a lot of competition 3-gun shooters go #1. Keep in mind, we are talking about reducing recoil for follow up shots (not accuracy) - like double tapping steel offhand at 100 yards.

I have a heavy buffer/spring (plus adjustable gas + brake) but I have to say I am coming around to the approach #1. It makes the gun about 4 ounces lighter, so you would think it would increase recoil. But having tried some of these setups, I have to say, I kind of agree they are a tad better. Follow up shots seem much easier. I cannot really put my finger on why this is, except maybe 556 does not have much recoil to begin with, so maybe the gun balances better.

The main downside of approach #1 I should note is $$$$$$$$. Personally I think adjustable gas block and brake will get you 70% of the way there without breaking the bank. JP low mass bolt carrier or Faxon light BCG = $$$$$$$.

The other main downside of #1 IMO is reliability. A lighter bolt and buffer could (will?) cause feeding issues when the gun is dirty. You cannot double tap steel if your gun jams.

A lot comes down to what you plan to do. For bench shooting, IMO, its technique technique technique. If you plan to run around and double tap steel from behind a barrier, these things might matter.

The usual goal is to minimize muzzle movement, reduce recoil/rearward movement, and preserve reliability, problem is the further you go to one end, usually the more the other 2 suffer. It's relatively easy to reduce the actual rearward/upward push from the bullet and gasses leaving the barrel, by redirecting the gas to the side, and upwards to keep the muzzle down. There is also significant recoil and muzzle movement from the Pound of bolt/buffer slamming back and forth, to reduce that you need to slow it down and/or reduce it's mass. The reason it weighs as much as it does is that the system is built to be reliable, it takes a lot of gas to get the carrier moving, the weight allows it to move at the correct speed, with plenty of momentum to plow through dirt and fouling, and it's less affected by different pressures from different ammo/temps.

If the bolt moves too fast, it can cause jams and excessive recoil, if it moves too slow, it can also jam, or fail to fully cycle. There is also a condition known as "bolt bounce" where the carrier slams into battery, then bounces back out of, or partially out of battery, it can cause jams, misfires, or potentially a kaboom, this is the reason for the loose weights in a buffer, as the bolt slams into battery, the weights hit a fraction of a second later, increasing the force just as the bolt would bounce, keeping it solid in battery. Reducing the gas flow from an adjustable block or increasing buffer/bolt weight slows down the carrier, increasing gas or reducing reciprocating mass speeds it up. I run an 8oz BCG with 1.5-2oz buffers and light springs in my 3 gun rifles, aluminum weights replacing steel/Tungsten, it takes very little gas to cycle at the correct speed, and recoil is exceedingly light, with practically no muzzle movement. It is reliable at a given temperature range with a single handload I run, it would have to be adjusted with an ammo change, large temp changes, or a few other factors to be reliable. My defensive builds generally run a 12oz FA BCGs with heavy flatwire springs and heavier carriers, I usually end up with H2 buffers (2 tungsten/1 steel weight) when running full gas, although I have a couple setup to run suppressed with adjustable blocks to compensate for added pressure, gives the right bolt speed with plenty of mass to plow through dirt, and handle a wide range of ammo.

Thanks to those who have responded so far. Great information.

The rattling/loose weights have been explained (I've never used a deadblow hammer of that design).

The recoil question seems more complex.
To clarify: 1) my application will be shooting from a bench at a range, with no high stakes reliability concern - this will not be a service rifle, nor will it be used to protect my home, or even to hunt with, 2) my goal is single-shot paper-punching precision only, from 100 to 600 yards, and perhaps later out to 1000 yards, 3) I am not concerned with recoil per se (its a 22), just as this affects single-shot precision, 4) I will not use a muzzle brake as installation would require serious turning down of the last 1/2" of the barrel (heavy SS barrel on order), which WOULD open up the bore in the most critical location. I have already purchased an adjustable gas block for this build. This 224V upper will be mated with my existing Rock River Varmint lower, which cycles and functions flawlessly, and has a 146 g. (5.15 oz.) recoil buffer weight as it came from RRA.

KRC said:

Thanks to those who have responded so far. Great information.

The rattling/loose weights have been explained (I've never used a deadblow hammer of that design).

The recoil question seems more complex.
To clarify: 1) my application will be shooting from a bench at a range, with no high stakes reliability concern - this will not be a service rifle, nor will it be used to protect my home, or even to hunt with, 2) my goal is single-shot paper-punching precision only, from 100 to 600 yards, and perhaps later out to 1000 yards, 3) I am not concerned with recoil per se (its a 22), just as this affects single-shot precision, 4) I will not use a muzzle brake as installation would require serious turning down of the last 1/2" of the barrel (heavy SS barrel on order), which WOULD open up the bore in the most critical location. I have already purchased an adjustable gas block for this build. This 224V upper will be mated with my existing Rock River Varmint lower, which cycles and functions flawlessly, and has a 146 g. (5.15 oz.) recoil buffer weight as it came from RRA.

Click to expand...

Recoil is subjective, in that, almost all guns recoil to some extent. I think that what others are trying to say is that it can be mitigated simply by proper technique.

Does recoil have an effect on accuracy? I'm not sure. I'm not a long range shooter.

My .02 is that for bench shooting, paper/steel punching to 600 yds, tune your adjustable gas block and call it a day. Get a good bipod, a good hold on your rifle, and a good cheek weld. 224V is not exactly a hammer. From a bench, your rifle wont even move with a good hold.

outrider58 said:

Recoil is subjective, in that, almost all guns recoil to some extent. I think that what others are trying to say is that it can be mitigated simply by proper technique.

Does recoil have an effect on accuracy? I'm not sure. I'm not a long range shooter.

Click to expand...

Well, recoil impacts accuracy through the "cringe" factor before you pull the trigger.

But as you say: technique, technique, technique

KRC said:

Thanks to those who have responded so far. Great information.

The rattling/loose weights have been explained (I've never used a deadblow hammer of that design).

The recoil question seems more complex.
To clarify: 1) my application will be shooting from a bench at a range, with no high stakes reliability concern - this will not be a service rifle, nor will it be used to protect my home, or even to hunt with, 2) my goal is single-shot paper-punching precision only, from 100 to 600 yards, and perhaps later out to 1000 yards, 3) I am not concerned with recoil per se (its a 22), just as this affects single-shot precision, 4) I will not use a muzzle brake as installation would require serious turning down of the last 1/2" of the barrel (heavy SS barrel on order), which WOULD open up the bore in the most critical location. I have already purchased an adjustable gas block for this build. This 224V upper will be mated with my existing Rock River Varmint lower, which cycles and functions flawlessly, and has a 146 g. (5.15 oz.) recoil buffer weight as it came from RRA.

Click to expand...

For precision builds, you probably are using a matched/fitted bolt, just use a decent mil-spec FA carrier built properly, and a standard buffer, then tune the gas till you are a click or two past the bare minimum to lock the bolt back on an empty mag, and done. Excess gas can affect accuracy to some degree, and can add stresses that can bring out issues with out of spec or tolerence stacked parts.

As far as recoil affecting accuracy, it generally doesn't, and some brakes can cause a shift in POI or exaggerate barrel movements. Light recoil can have some benefits, mainly that you can stay on target, watch your rounds hit, and there is less movement to re position for the next shot. Where it is critical is in action shooting, when I run a 3 gun stage, having a rifle with the least ammount of muzzel movement possible is a big advantage, I can put my crosshairs on a target, and just blindly double tap fast as I can pull with a minimal spread between shots, and a better chance of getting both shots together in the center. This allows me to move to the next target faster, reduces split times which reduce stage times, which puts my name higher on the board and prize table.