The Original CZ Forum
GENERAL => Ammunition, questions, and handloading techniques => Topic started by: Vinny on August 12, 2018, 08:34:02 AM
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I've been using S&B SB9B 124gr FMJ in Carry Optics for local matches; CZ P-07 and SIG 229 with 4"+or- barrels.
Trying to calculate PF.
But, S&B's ballistics specs are rated with 6" barrel.
Anyone know 'roughly' how much muzzle velocity decreases with 2" shorter barrel?
I've tried a bunch of off-the-shelf ammo and for me this ammo seems to work best; and their 115gr is OK too. As a 'Super Senior' I'm just happy RDS allows me to still compete with my 'ol eyes.
Thanks for any 4" velocity or PF info, Vinny
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Since the S&B appear to be listed at 1181 fps (146 PF) there is very little chance that with a 4" barrel in decent condition that you will loss almost 180 fps, but the only way to be sure is to chrono YOUR pistols.
The next match tell the other competitors you want to check you loads and perhaps someone will arrange to let you tag along at their next chrono session.
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Since the S&B appear to be listed at 1181 fps (146 PF) there is very little chance that with a 4" barrel in decent condition that you will loss almost 180 fps, but the only way to be sure is to chrono YOUR pistols.
The next match tell the other competitors you want to check you loads and perhaps someone will arrange to let you tag along at their next chrono session.
Found this video of S&B 124gr chrono with 4 different length barrels from 3" to 7.72". https://www.youtube.com/watch?v=mSsz6XdUwmE
The 3.6" barrel FNS 9c chronos out at 1024fps for 126.98PF.
Was hoping someone on the Forum has chrono'ed their P-07 or SIG P229 with S&B 124 FMJ already. If it's over 130PF I guess I'd feel safely 'legal'.
Your suggestion of testing with my pistols is even better. But our local matches, even monthly sanctioned ones don't chrono; so I'd have to tag along at a larger regional sanctioned match. Or, find a range with a Chrono and RO that knows how to calibrate and test.
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If your matches don't chrono, then it doesn't matter much.
Even if you were using the same length barrel, it's still not a reliable calculation. Too many factors. Different barrel - - different velocity, even at the same barrel length.
At different barrel lengths, you'll get different results with different powders.
AND you cant count on manufacturer specs being accurate.
Pretty much, if your match directors don't care, but you do (commendable), you'll have to find a chrono.
Maybe take this as an opportunity to travel to a bigger match where you'll be chronoed. ;)
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If your matches don't chrono, then it doesn't matter much.
Even if you were using the same length barrel, it's still not a reliable calculation. Too many factors. Different barrel - - different velocity, even at the same barrel length.
At different barrel lengths, you'll get different results with different powders.
AND you cant count on manufacturer specs being accurate.
Pretty much, if your match directors don't care, but you do (commendable), you'll have to find a chrono.
Maybe take this as an opportunity to travel to a bigger match where you'll be chronoed. ;)
All good advise; I especially like the one about going to a major match, hopefully with Carry Optic competition. 8)
I'd still like to hear from some that are running S&B 124 FMJ ammo and have chrono either their P-07 or SIG 229. I'm sure if I use my SP-01 Tactical with longer barrel there's no issue making PF.
Yeah, I know serious competitors are hand-loading or buying competition ammo.
I'm only looking for a good, affordable, ammo that comfortably meets PF.
I like the way this shoots, and it's priced right!
I like to shoot, a lot. ;D
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I'm only looking for a good, affordable, ammo that comfortably meets PF.
I like the way this shoots, and it's priced right!
I like to shoot, a lot. ;D
Check out the Atlanta Arms remanufactured ammo in "cases" (1000 piece lots). That's all ammo meant for competition, reloaded by competitors for competitors.
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I'm only looking for a good, affordable, ammo that comfortably meets PF.
I like the way this shoots, and it's priced right!
I like to shoot, a lot. ;D
Check out the Atlanta Arms remanufactured ammo in "cases" (1000 piece lots). That's all ammo meant for competition, reloaded by competitors for competitors.
Thanks Wobbly,
I saw another post from you and I did check out the reman ammo from Atlanta Arms. Still seems to be about 10 cents/round (to my door) more than what I'm paying for the S&B 124 FMJ ($.19/round, after tax, to my door). And I'd still have to know velocity from my guns. But, I may try a case anyhow just to see if the $80-$100 difference is worth it.
The S&B ammo is working for me; tight groups, easy recoil and back on target. It's new brass, 1,000's of rounds without a hiccup, and pretty clean too. I just want to be sure I'm at or above minor PF.
Anyone out there with S&B 124 FMJ chrono results with a P-07 or SIG P229 RX??
Yeah, I know there's variance; just want to know I'm comfortably over 125PF.
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I was at the range today chronoing a bunch of stuff.
122gn Acme flat point at 1.04 OAL Out of Shadow, 4.5" barrel, Out of an M&P Shield, 3.1" barrel, 1014 fps. Out of an M&P Compact, 4"barrel, 1087 fps. This was with 4.5gns of WSF, a fairly slow powder for 9mm USPSA shooters. Though if your S&B stuff is getting 146 pf out of a hand gun, I'd expect they are using something similar to WSF on the speed chart.
I did the same thing with another load. 147gn Blue Bullet flat point with 1.12 OAL at 3.4 gn of HP38. Shadow, 929 fps, Shield 852, M&P Compact 906.
YMMV. But this probably puts you in the ball park. I've never heard of someone shooting factory 124gn 9mm going sub-minor at a major match.
If you are nervous, I recommend you find a friend with a chrono.
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I was at the range today chronoing a bunch of stuff.
122gn Acme flat point at 1.04 OAL Out of Shadow, 4.5" barrel, Out of an M&P Shield, 3.1" barrel, 1014 fps. Out of an M&P Compact, 4"barrel, 1087 fps. This was with 4.5gns of WSF, a fairly slow powder for 9mm USPSA shooters. Though if your S&B stuff is getting 146 pf out of a hand gun, I'd expect they are using something similar to WSF on the speed chart.
I did the same thing with another load. 147gn Blue Bullet flat point with 1.12 OAL at 3.4 gn of HP38. Shadow, 929 fps, Shield 852, M&P Compact 906.
YMMV. But this probably puts you in the ball park. I've never heard of someone shooting factory 124gn 9mm going sub-minor at a major match.
If you are nervous, I recommend you find a friend with a chrono.
Smitty,
That's helpful info. There's another site with similar results as yours called 'Ballistics by the Inch' comparing different guns with different barrel lengths and different ammo. 'On average' the difference in velocity between 4" and 6" seems to be 8-10%. So, my 'guess' is from 6" @146PF to 4" should be low to mid 130's PF.
I'm probably fine, but hearing from someone who's chronographed a P-07 or P229 with this ammo would be reassuring.
I just didn't want to reinvent the wheel if it's already been done.
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Just as a side note how is their name pronounced? I grew up in a bilingual household speaking both english and french and I thought it was a french name pronounced SELL-yay and BELL-oh. But then I read that they have a factory in the Czech Republic but those don't look like slavic names to me. So what ethnicity is Sellier and Bellot and how is it pronounced?
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Just as a side note how is their name pronounced? I grew up in a bilingual household speaking both english and french and I thought it was a french name pronounced SELL-yay and BELL-oh. But then I read that they have a factory in the Czech Republic but those don't look like slavic names to me. So what ethnicity is Sellier and Bellot and how is it pronounced?
I don't know...but I say the name like you phonetically pronounced it.
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It's pronounced..... Ess & Bee.
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