FN57 and AR57 Chronograph Data, plus more!!!!

[KiloTrooper]

Of note: went to the range last night and did a test with SS197, and SS195 with my new Chronograph. Here are the results:
temp. 72, low humidity, wind 1-2 mph 1800-1945 hours EDT

SS195
AR57: 2368, 2398, 2393, 2385 & 2415 fps Avg. 2391 "Factory": 2470 / Difference -170 fps
FN57: 1926,1937,1987, 1932, & 1924 fps Avg. 1941 "Factory" 1970 / Difference -29 fps
450 fps difference, 40 fps gain per bbl"
SS197:
AR57: 2070, 2032, 2063, 2089, & 2080 fps Avg. 2066 "Factory" 2100 / Difference -44 fps
FN57: 1672, 1654, 1662, 1670, & 1664 fps Avg. 1664 "Factory" 1675 / Difference -11 fps
402 fps difference, 36 fps gain per bbl"

Also tested:
9mm: 5" bbl consistently gave + 30 fps over 3.8" bbl
.380acp: Sellier & Bellot gave an avg of 998 fps out of 3.75" bbl- my favorite food for the PK380 Remington came in at 957 fps avg.
.243 Winchester: Hornady Custom 58gr V-max moly Avg of 3467 fps vs factory stats of 3750 fps.
** found that there is an average of 260 fps velocity loss between factory stats on a 24" bbl, vs. my Rem 700 VTR 22" bbl using 3 types of Hornady ammo including 95gr SST Custom and 80 gr. GMX Superformance

Kilo

[SoCal Gunner]

I love reading posts like this...

You should keep it up and post more results if and when you come across some of the other 5.7 variants.

[KiloTrooper]

thanks

[WA-Tom]

To have relevant data you need to include barrel lengths. How long of a barrel did your AR57 have?

[fatherfoof]

We always appreciate members taking the initiative to share data. Thanks!

[AKStevoUSN]

To have relevant data you need to include barrel lengths. How long of a barrel did your AR57 have?

450 fps difference, 40 fps gain per bbl"

Do the math

[KiloTrooper]

16"

[WA-Tom]

Thanks! Thats what I thought, but I could not assume you were not using an NFA length rifle barrel.