Originally posted by Fredman
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Berger 130 AR Hybrid OTM Tac's & CFE 223
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This Really is a Cool bullet. Been checking it out online since it's inception. I would like to slice 1 lengthwise to see what's really under the skin. Tapers, & base units copper size , wt. etc.
Anyone have an extra, or 2 to donate? I can check the viability of a 115-120 unit, while slicing 1 open. Open minds lead to great offerings.
Sierra has the same idea in the OTM idea. Hunting version.Last edited by sneaky one; 01-26-2016, 01:52 AM.
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Originally posted by 1911man View PostIm betting you could still get good groups with XBR but probably not near the velocity you would get with Levr or CFE
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It's about keeping current, and an open mind on all that surrounds this 12-13 yr. old round. It's up to us- the many that like this caliber-size - etc.,,, and the willingness to accept the fact
that a few will push Ahead on some subjects. Grrr Max is 1- Thoughts ?
kmon, yeah all the known data is -proven. I busted a many myths on This round. Trial & Error is best for a Many,,- follow the herd -- is the rest. No problem either way. Buy a Grrr. ! Shoot.
Team effort has always been my goal for the GRRRR gang, !!! Go!! Find something new ASAP.
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I returned to the range, today, and shot a couple of ten round strings of 30.6 gr. CFE223.
Temps are 24 ' warmer (37 'F then, 61 'F today) and, not surprisingly, I saw an increase in MV. For the 24 'F increase, I picked up an average of 31 fps, or 1.3 fps per ' F.
Same components as before: Hornady cases, CCI 450 primers, Berger 130 AR Hybrid OTM's, seated at 2.260".
the first 10 round string went over the chronograph and resulted in the following:
Code:# FPS FT-LBS PF 10 2404 1668.51 312.52 9 2406 1671.28 312.78 8 2420 1690.79 314.6 7 2396 1657.42 311.48 6 2389 1647.75 310.57 5 2366 1616.17 307.58 4 2411 1678.24 313.43 3 2377 1631.24 309.01 2 2397 1658.8 311.61 1 2388 1646.37 310.44 Avg StdDev Min Max Spread True MV (10' to chronograph) 2395.4 16.1 2366 2420 54 2399
Shooting the group at 100 yds. with the next 10 rounds proved challenging, as winds were steadily increasing. With winds at 20 mph and gusting to 27, the target stand was swaying significantly, causing the sight picture to move a full inch or more, so I had to time the shots as best I could.
After the 7th shot, though, I cut my losses and was happy to get what I did.
Shot at 100 yards. Grid is .10", so the full group size was just under 1", CTC, and the cluster of five runs right at .5" CTC at its widest.
For the conditions, I think this was acceptable, especially since I could feel the table moving beneath me.
Thanks for the read.If it's true that we are here to help others, then what exactly are the others here for?
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That would be a bad 25 yard group under those conditions, but I'm guessing the target was a tad further out.shootersnotes.com
"To those who have fought and almost died for it, freedom has a flavor the protected will never know."
-- Author Unknown
"If at first you do succeed, try not to look astonished!" -- Milton Berle
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Originally posted by 1911man View PostThis is awesome data. Are you seeing any pressure signs at with this charge weight? I would imagine not since you are not even close the max charge for CFE and this size bullet. Good stuff man, keep it coming.If it's true that we are here to help others, then what exactly are the others here for?
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Originally posted by sneaky one View PostThis Really is a Cool bullet. Been checking it out online since it's inception. I would like to slice 1 lengthwise to see what's really under the skin. Tapers, & base units copper size , wt. etc.
Anyone have an extra, or 2 to donate? I can check the viability of a 115-120 unit, while slicing 1 open. Open minds lead to great offerings.
Sierra has the same idea in the OTM idea. Hunting version.
Well, I finally got out to shoot the modified Berger AR Hybrids. Gotta say I wish Berger would make these in the 115gr neighborhood. The four bullets you modified weighed 112.6, 114.6 (2) and 114.9 grs. With a charge of 28.5 gr of IMR 8208 XBR, and seated to 2.260", the following velocities were recorded through a 22" BHW barreled rifle.
2694, 2700, 2764 and 2687 for an averaged MV of 2691 fpsNote: While I understand that the form factor will not be quite the same, being that you trimmed their length, it should still prove a reasonably close figure for these purposes.
SD = (W / 7000) / (D^2)
G7 BC = SD / G7 FF
Where:
W = weight in grains
D = bore diameter in inches
G7 FF (.928, from Berger's 130 AR Hybrid OTM data specs)
I calculated both original and new weights.
Code:W D SD G7 FF G7 BC 130 0.264 0.266 0.928 [B]0.287[/B] (reference calculation) 114 0.264 0.234 0.928 [B][COLOR="red"]0.252[/COLOR][/B] (extrapolated BC)
Code:Range Drop Wind. Veloc. Energy (yards) (in) (in) (fps) (ft-lbs) 0 -2.5 0.0 2706 1853 100 0.0 0.0 2527 1616 200 -3.0 1.0 2354 1402 300 -12.2 3.0 2188 1212 400 -28.7 6.2 2030 1043 500 -53.7 10.7 1877 892 600 -88.5 16.8 1731 758 700 -135.0 24.5 1589 639 800 -195.3 34.3 1453 534 900 -272.1 46.3 1322 443 1000 -368.9 61.0 1199 364
Thanks for the chance to evaluate, sneaky.If it's true that we are here to help others, then what exactly are the others here for?
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