The Ruger carbine that they used must be a total piece of shit, because the 147 grain loads that I've chronographed showed a significant increase in velocity when fired from a quality 16" AR-15 carbine such as the Colt 6450/6951 with low round counts on them, when compared to handgun velocities.Originally Posted by Suvorov
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Member of the General Population
I really need to test it out of my m92. I'm guessing it'll hit 1700fps
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Don’t know? Maybe different bolt weights delaying blowback but the general idea I think was that the powder was burned up before the bullet left the gun and the projectile actually began to slow before leaving the barrel. This is what they posted here: https://www.luckygunner.com/lounge/s...iber-carbines/The Ruger carbine that they used must be a total piece of shit, because the 147 grain loads that I've chronographed showed a significant increase in velocity when fired from a quality 16" AR-15 carbine such as the Colt 6450/6951 with low round counts on them, when compared to handgun velocities.
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Anyhow, it’s good to have your data points.
What seems to be the ticket would be a .357 Sig HP bullet in a 9mm case as it is optimized for the 1300-1400 fox range……. But that kind of defeats the ability to shooting the same ammo your pistol shoots…
In all blowbacks guns case extraction begins before the bullet exits the muzzle, and this theoretically decreases the pressure behind the bullet that is the force accelerating it.
But this extraction is a small fraction of an inch so the actual difference in muzzle velocity will be negligible.
It has to be very small for proper functioning, otherwise you would see ruptured/badly bulged cases and very perceptible gas in the face.
If a firearm exhibits lower muzzle velocity than expected there must be other reason.
Most likely caused by a dimensionally ''out-of-spec'' bore, were I to guess. Just a few ten-thousandths (on the ''high'' side of tolerance) can have a tremendous effect.
''Politics is for the present, but an equation is for eternity.'' ―Albert Einstein
Full disclosure per the Pistol-Forum CoC: I am the author of Quantitative Ammunition Selection.
Those 16.1" Ruger velocities are low, My 9x19 chrono data out of a 16" PSA Colt Pattern upper..
My results...
Speer 124gr GD...................................1376fps
Speer +P 124gr GD..............................1458fps
Federal, 124gr HST...................................1335fps.. oddly a little smokey
Federal, +P 124gr HST..............................1422fps
Federal, 147gr HST.................................1124fps
Federal, +P 147gr HST..........................1182fps
FWIW... The bonded bullets "tended" to shoot better from my barrel. Fluke ? Maybe... but I can't help but wonder.
Enough so, that I settled on the Federal, +P 135gr Tactical Bonded HP......1345fps.... for SD use.
A bunch more here... 129 OEM Factory 9x19 loads chrono'd
https://www.ar15.com/forums/ar-15/-/16-712312/?page=1&anc=7429025#i7429025
Last edited by bfoosh006; 08-15-2023 at 07:43 PM.
I wonder if there is something about the Ruger that is causing the low velocities?
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