Recoil: 14.5" mid length vs. 16" intermediate

[voiceofreason]

Anyone have used both?

Curious how the recoil impulse of a 14.5" mid length compares to a 16" intermediate.

And how they would compare to either a 16" carbine, ieColt or a 16" mid length ieBCM?

16" carbine or mid with an A5?


Think BCM vs KAC (take cost, mil spec, proprietary out of the equation please)

Cursory research for a lightweight non-NFA low recoil gun, for a small statured but experienced shooter.

Thinking one of the above with an AFAB.

For defensive, range, training, and just getting the gun to fit the shooter who prefers a lighter gun (reliability is a must)

Anything thoughts and experience would be appreciated. Open to alternative advice as well.

[17K]

All about the same since everyone but Colt opened up the gas ports.

An old Mod1 and an old BCM 14.5” mid were SUPER barrels, but needed 5.56 ammo and a CAR buffer to run in all conditions.

Port size matters more than location.

I’m not huge on the A5 as I don’t think they do anything for reliability and I just don’t like the clunky recoil of a heavy buffer.

[MegademiC]

Anyone have used both?

Curious how the recoil impulse of a 14.5" mid length compares to a 16" intermediate.

And how they would compare to either a 16" carbine, ieColt or a 16" mid length ieBCM?

16" carbine or mid with an A5?


Think BCM vs KAC (take cost, mil spec, proprietary out of the equation please)

Cursory research for a lightweight non-NFA low recoil gun, for a small statured but experienced shooter.

Thinking one of the above with an AFAB.

For defensive, range, training, and just getting the gun to fit the shooter who prefers a lighter gun (reliability is a must)

Anything thoughts and experience would be appreciated. Open to alternative advice as well.

17k hit most of it.
Location and barrel length are useless by themselves. You have to compare the entire system.
System: barrel length, gas port size, location, buffer spring, buffer weight.

[Stickman]

Anyone have used both?

Curious how the recoil impulse of a 14.5" mid length compares to a 16" intermediate.

And how they would compare to either a 16" carbine, ieColt or a 16" mid length ieBCM?

16" carbine or mid with an A5?


Think BCM vs KAC (take cost, mil spec, proprietary out of the equation please)

Cursory research for a lightweight non-NFA low recoil gun, for a small statured but experienced shooter.

Thinking one of the above with an AFAB.

For defensive, range, training, and just getting the gun to fit the shooter who prefers a lighter gun (reliability is a must)

Anything thoughts and experience would be appreciated. Open to alternative advice as well.

While I have plenty of 14.5 and 16 midlength weapons, I only have one intermediate, and one 16" rifle length. Its hard to get into huge comparisons with that little involvement. What I can tell you is that there is more going on than just barrel length or port location. I know its already been stated above, but I am in complete agreement.

It would be important to know what sort of ammunition was going to be used. Cheaper stuff like Wolf might not cycle a weapon that 5.56 cycles just fine. The muzzle device, weight, balance and buffer weight (and type) are portions that are pretty obvious. However, with the advent of altering your port size, adjustable gas blocks, and even gas tubes which alter gas flow to your desired end goal.... its a new world for guys who want to play around and dial things in.

[voiceofreason]

ammunition used: .223 AE; 5.56 IMI; Wolf Gold .223; 64gr Gold Dot; 77grSMK; NO Tula, Bear, Wolf steel or anything surplus

buffer: I use H or H2 depending on the gun, H for defensive use, H2 for soft shooting range use and 5.56 in the 16" carbines (S&W M&P for example)

muzzle device: A2 birdcage, though I am thinking of moving to AFABs

buffer spring: change out a USGI type spring every 3k or so, sometimes 4k; considering trying a Springco Blue with the H2 for a 6920 as the recoil is noticeably higher when running 5.56 than a middy

So basically, it doesn't really matter anymore given everyone is running a larger port size except Colt?

I was basically comparing KAC Mod 2 16" or 14" to BCM middy or 6920 carbine.

[AndyLate]

I have 2 lightweight 16" uppers - 1 BCM midlength gas and 1 Black River Tactical Optimum gas. Subjectively, the BRT recoil is "flatter" but the difference is subtle.

I cannot provide any hard data to assist your decision.

I will opine that either is a great choice if you are not trying to wring out that last .01 second in competition.

Recoil impulse is noticeably sharper/more abrupt with either my LMT 14.5 or my son's 16" PSA carbine (with BRT corrected gas port) and I would expect a Colt 6920 to be very similar.

Andy

[17K]

I notice the recoil of a 6920 to be a little quicker than a 16" mid, but years of shooting both and I just never could consistently wring out more speed from the mids. So for me, it's a case of feels not equaling performance.

I was actually shooting a stock 6920 alongside a 16" BCM mid recently and they were really close on recoil feel.

[turnburglar]

I think my 16 mid is lighter recoil than my 14.5 mid. I find that subjectively a longer barrel is 'nicer' to shoot in the AR's. For a seriously recoil sensitive shooter a 16 mid is not a big deal. My wife shoots her BCM all day long but hates the AR10's.

[Clint]

We make both barrels and they're both OPTIMUM configurations for general purpose use.

So between the two, they're essentially the same as long as they have properly sized gas ports, which is the most important factor.

A more general question might be "what's the difference between a barrel with an optimal gas system configuration and one without?"

Optimum configurations allow the widest range of ammo to be used with the same gas port size.

To put it plainly, they don't need the gas ports over sized in order to reliably run low power ammo vs hot ammo.

[Sry0fcr]

Anyone have used both?

Curious how the recoil impulse of a 14.5" mid length compares to a 16" intermediate.

And how they would compare to either a 16" carbine, ieColt or a 16" mid length ieBCM?

16" carbine or mid with an A5?


Think BCM vs KAC (take cost, mil spec, proprietary out of the equation please)

Cursory research for a lightweight non-NFA low recoil gun, for a small statured but experienced shooter.

Thinking one of the above with an AFAB.

For defensive, range, training, and just getting the gun to fit the shooter who prefers a lighter gun (reliability is a must)

Anything thoughts and experience would be appreciated. Open to alternative advice as well.

Allow me to be the voiceofreason here, you're really overthinking this. The AR platform is already pretty lightweight and light recoiling. If this is for an experienced shooter, chasing incremental feelz of the recoil impulse probably isn't really worth the time, effort and money for a "defensive, range, training" gun where "reliability is a must". Get a Colt 6720 (or similar pencil barrel upper with reasonable gas port), then try not to hang a bunch of shit off of it. I put together one for my 11 year old with a Magpul K stock and grip to get the LOP a bit shorter. Also, I didn't weigh it, but I'm almost certain that putting on a low-pro gas block and 10.75" URX actually saved weight over the FSB and double heat shield handguards on ours.

[voiceofreason]

Always appreciate the great advice here on M4C. Thank you all.