12.5 inch barrel vs 13.7 inch barrel velocity

[SHARPSHOOTER282]

I’ve built a 12.5 mid length gas system and a 13.95 mid length. I can get you some fps with Winchester white box, pmc, or federal 223 and 5.56. It might be a while, but happy to run some numbers next time at the range with chrono.

Cheers , that would be cool

[mig1nc]

Cheers , that would be cool

Would be extra cool if they are both from the same series from the same manufacturer.


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[Strikefirst]

I have a 12.5 and 13.9 criterion core...I can get you velocities as soon as this lousy Michigan weather breaks.

[SHARPSHOOTER282]

I have a 12.5 and 13.9 criterion core...I can get you velocities as soon as this lousy Michigan weather breaks.

sweet

[Strikefirst]

American Eagle M193 average velocities

12.5 criterion core average 5 shots 2854

13.9 criterion core average 4 shots 3062

Chrono 15 feet downrange

[1168]

American Eagle M193 average velocities

12.5 criterion core average 5 shots 2854

13.9 criterion core average 4 shots 3062

Chrono 15 feet downrange

Don’t bank on reproducing that with 2 other barrels, but thanks for sharing your results.

[titsonritz]

That is pretty impressive difference for 1.4” spread.

[Strikefirst]

The 13.9 only had 200 rounds down it when tested. Was a new builds. The 12.5 had about 500. 13.9 was shot suppressed yhm turbo t3. 12.5 shot cold u suppressed

13.9 handloaded 62gr gold dots 2.260 oal. Light crimp arplus 24.0 gr. 2766 fps avg

[mig1nc]

So, this is completely unscientific, but today my buddy chronod his 13" X95 SBR and averaged 2919 with American Eagle 55gr 60 degrees at around 400 feet elevation.

Same weather my 13.7" ballistic advantage did 2865 with M855.


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[Strikefirst]

So, this is completely unscientific, but today my buddy chronod his 13" X95 SBR and averaged 2919 with American Eagle 55gr 60 degrees at around 400 feet elevation.

Same weather my 13.7" ballistic advantage did 2865 with M855.


Sent from my iPhone using Tapatalk Pro

My elevation was about 820.