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Discussion Starter #1 (Edited)
I'm hoping this can be included in the bullet info gathering threads. As per all the others, no questions or commentary; start another thread if you need to. Please just post the facts or your experience with the bullets. How they performed on game, the accuracy of the bullet, load data, etc...

If you don't have any experience please let those that do have experience provide the info for others to learn from.

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As of this posting, these only appear to be available as pulls via Rockey Mountain Reloading which is run by longdayjake on this forum. There is very little info regarding these bullets including what they were being loaded in or for. Jake's only comment on them so far has been

... They are .2765 in diameter... Most everything we get comes from the Federal plant in Lewiston.
In an effort to get some info coming in I purchased 500 with the intention of splitting them up with some other members and doing some testing.

For starters I took a random sample of 51 pieces and measured weight, diameter, and length.

Weight

Low- 74.38
High- 76.04
Ave- 75.31

Diameter

Low- .2740
High- .2760
Ave- .2749

Length

Low- .7555
High- .7720
Ave- .7638

Here's why I ended up doing 51; there was an outlier, which could be the reason they were pulled. On bullet #42 I got a short/light one that I excluded from the measurements above. It weighted 67.08 grains and was only .6920" long, with the diameter right at .2750". Visually you'd never notice it and loading it would probably be fine as pressure should be reduced with it, but still, something to consider.

Here's a photo of how they look right out of the package.


And then how they look after an acetone bath and tumbling with walnut media and polish.


In both of the above photos you can see very minor pull marks, and some exhibit broken edges on the bases. It's very possible that the bases could play into long range accuracy issues, but I just don't see these being used in that capacity anyway.

Next up is a bullet crushed lengthwise in a vice to show their frangible composition. I'm by no means a metallurgist, but they're appear to be some sort of a copper matrix with perhaps tin? Regardless, they appear pretty typical of other frangible rounds that I've seen.


Here's a cross section, although its a bit deceiving as it makes it look like a traditional solid copper in the way it polishes. The top left and bottom right flaws are from my cutting and polishing and can not be attributed to the bullet itself.


Here's a comparison for shape and lengths based on some other .277 diameter bullets I had close at hand.
From left to right: 75gr Frangible, 82gr Raptor, 90gr Sierra HP, 90gr Gold Dot, 110gr VMax


Load testing from me will be coming in a couple of weeks and I'll be starting with Rel7 from a 20" Bison barrel with intermediate length gas system.
Stay tuned for more.
 

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Discussion Starter #2
Made it to the range today to test my first ladder.
I've never worked up or created a ladder before so go easy on me if something looks unconventional.

Bison 20" with intermediate length gas.
Federal once fired brass
Wolf .223 primers
Reloader7
COAL 2.274"
"Medium" crimp with LFCD

Charge- 28.6
2930
2917
2949
2962
2930
AV- 2938
ES- 45
SD 17.78
MOA- 4.69
Notes- short stroked on round #3 and didn't lock back on empty mag

Charge- 29.0
2956
2996
3003
2962
3003
AV- 2984
ES- 47
SD- 23.10
MOA- 3.79
Notes- cycled perfectly, no ss

Charge- 29.6
3051
3023
3051
2996
3009
AV- 3026
ES- 55
SD- 24.74
MOA- 3.52 (best full group)

Charge- 30.2
3086
3093
3086
3086
3093
AV- 3089
ES- 7
SD- 3.83
MOA- 6.44

Charge- 30.5
3129
3129
3108
3122
3137
AV- 3125
ES- 8
SD- 10.89
MOA- 3.81

Charge- 30.9
3182
3182
3212
3174
3182
AV- 3186
ES- 38
SD- 14.72
MOA- 5.54 (3 shots into .99 MOA- best sub group)

Charge- 31.5
3205
3228
3223
3189
3182
AV- 3205
ES- 46
SD- 20.23
MOA- 5.86

Charge- 31.9
3228
3236
3220
3220
3252
AV- 3211
ES- 84
SD- 33.75
MOA- 8.98

(As a comparison factory Hornady 110gr HPBT were averaging 2728fps for me today.)

General impressions- No significant pressure signs on any of those loads. There were VERY minor swipes, but way less than what most of the factory once fired federal brass shows anyway. As I was getting up into the 31 grain range I was having to use a vibrating tooth brush to get the powder settled. Using that technique I was just starting to crunch powder at 31.9 grains, so that's just about it capacity wise with Federal brass. I think with another brass, maybe Hornady/S&B, 3300+ would be easy. I'm absolutely not the one to be testing for accuracy, so don't let my groups carry too much weight. I was only shooting at 55 yards but the wind was blowing 15-20mph from every direction. Just a hunch, but I think if one were to try for accuracy with these it would probably be important to cull the ones with compromised base edges.
 

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Discussion Starter #3
Well, I refined my ladder to focus between the lowest SD load and the load with the best accuracy, which ended up being roughly 30-31 grains in 0.2 grain increments. Additionally, I only loaded bullets with pristine bases. Still got similar result to the first outing, as in 4-7moa groups. Which leads to a question. These have all been lightly crimped with a LFC; considering the bullet's construction, is it likely that the crimp is compromising the bullet? All target holes are nice and round, with no sign of them coming apart in flight. In the ten round 30.24gr string I did shoot three rounds touching, measuring 0.47moa, but they were high and left of the groups center, so I'm going with it being a fluke.

On this particular day I was shooting TNT groups that measured as low as .621" at 100yrds, which reassured me that my brain and trigger finger are capable of working together!

Any thoughts? Anyone else given these a try yet or did I scare everyone off?!
 

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Mi just dropped the price on them. We only have 1500 left and they didn't sell well so we won't be getting more. $60 for 500 shipped now.
I am still interested. As these arent hunting bullets they dont appeal as much. That said, I may order some to ring the gong with.

Here is a guess... If the frangible ammo was produced using sintering which is difficult to produce uniform shaped projectiles. And the tumbling appears to have taken chunks off.

Interesting point on the crimp. Instead of doing a crimp what about using locktite? Ive used that for reloading 5.45x39 steel case.

Thanks for documenting this.
 

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Added to sticky. Please stick with data and results per OP.
 

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I still have these to test, as soon as I get some free time.... Lol
 
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