Buffalo Bore 357 Magnum Loads

[davesmyrnaga]

I’m getting excellent velocities from BB Heavy 357 Magnum 10 shots on each sample:

19C/20 158gr JHP (looks like Hornady XTP). 19K/20 140gr Barnes lead free
AVG SD HI LOW AVG SD HI LOW
S&W 5” 27-2. 1440 17.66. 1473. 1404. 1535. 34.54. 1572. 1468
S&W 5” 27-2 (ported). 1373. 28.95. 1402. 1300. 1464. 24.83. 1491. 1413

My results compare well with velocities on the box:
1475fps. 1550fps
Extraction effort: Stiff not dropping out. Had to bang extractor
Accuracy with two hands standing at 30 ft:
Great Great

I’ve never ever gotten close to these velocities. I get ~1250fps with 158gr with 2400, 110 and 296. Haven’t tried LilGun or 4227.
Should I give up reloading 357 and just buy BB 357 or what?

 

[troy fairweather]

could be just a better fit to your bore. what about cfe pistol is that used in 357s. what do u need them for if hunting them buying bb is not to bad but for range fun it will get pricey

 

[Zaydok Allen]

Are you taking really long shots? To me velocity is important, but there's certainly a point of diminishing returns.

Sticky extracting rounds aren't something I want to shoot on a regular basis.

I guess I'd be more inclined to step up my loads in extremely small increments until a hint of pressure signs are evident. Then back off slightly. I'm not advocating exceeding published load data. Increase any load at your own risk.

 

[Toprudder]

Difficult extraction is no fun. I would never want to make loads that I have to bang out of the cylinder. The fact that they may go faster is moot.

1250fps is a little bit more than the highest velocities I have gotten out of my 5" Ruger. As long as they are accurate, that is plenty fine for me.

 

[murf]

clean the chambers real good. you are at the top of the pressure range with that bb load. carbon fouling affects more the high pressure rounds because the cases spring back a lot less and the carbon builds up between the case and chamber. the sticking problem should get progressively worse if this is the case (no pun intended).

luck,

murf

 

[cheygriz]

Sticky??

No thanks. I'll pass.

 

[Eddietruett]

I agree with Toprudder. 1250fps with a jacked bullet should be fast enough for about any purpose I can think of. Between 1250-1300 is what I get with jacketed bullets out of my 8 3/8” Mod 686 with 158gr bullet. I can get a fair amount faster with coated lead. I get around 1325-1350 with a 180gr HyTek Coated Lead Bullet with 13.6gr of H110 that’s my hog hunting load and actually 1250fps is fast enough, but the 1325fos load is the most accurate so I’ll stay with that

 

[davesmyrnaga]

I guess it’s the challenge: can I duplicate factory loads and maybe get better accuracy. With Buffalo Bore this may not be possible.

 

[tightgroup tiger]

With Buffalo Bore this may not be possible.

They blend different powders together to get their velocity at what they consider a safe pressure, usually maximum pressure. Their recipes are deep dark secrets.
Good luck!

 

[labnoti]

The way I understand Buffalo Bore loads and Hornady Super Performance for example, is they use proprietary powder blends that maximize velocities without exceeding peak pressure limits. Essentially, they're using a custom powder blend for the cartridge that you could not formulate for reloading unless you blended powders and measured pressures on the results. Powders like H110 or W296 are one-size-fits-many. Hodgdon could sell a powder formulated specifically for 158 gr. .357 Magnum loads, but it wouldn't be just as ideal for .327, .41, .44, .45 etc. There are already a lot of powders and different cartridges available and the process of testing and publishing load data for all the conceivable combinations is labor consuming. Customizing propellant for a specific load might be practical for Buffalo Bore who caters to ballistic spec-sheet shoppers, or for Hornady.

 

[Walkalong]

Yep, IMHO you would just be chasing trouble.

 

[labnoti]

Powder blending shouldn't be seen as a dark secret, but it's not something that can be attempted without test equipment (meaning powder chemistry equipment that I'm not familiar with, and a test barrel in a protective cell with pressure transducers). Most powder is blended. When a batch of Powder X is produced, it's measured. If it's a little above or below spec, powder from a previously produced batch of alternately low or high spec is blended in until the batch measures between the high and low limits of spec. That's how consistency is ensured from one powder lot to the next.

Because guns have pressure limits, cartridges have peak pressure limit specifications. The key to getting the highest velocity within a peak pressure limit is to maximize the area under the pressure/time curve. Powder has a number of meaningful characteristics, but one that's easier to understand is "burn rate." Burn rate isn't a constant, but it varies with pressure. What determines burn rate is not only the bases, proportionally, how much nitrocellulose and nitroglycerin are used, but also the deterrents, the things that slow combustion. I speculate, but do not know, that proprietary powder blends are formulated by blending different powders to achieve more than one pressure peak over the combustion time while still not exceeding the peak spec. Another way of oversimplifying it would be to think of blending the slowest possible powder for a particular load without it being too slow.

 

[cheygriz]

Powder blending bad.

Powder blending make fingers go away.

 

[horsey300]

My practice load, plinking load, fun playful load uses bullseye in a .38 special case, my hot magnum, killing stuff yesterday load uses 2400, i don't get sticky cases, i get good accuracy, and i still get enough heat to get the job done. Haven't chronographed them yet, but with a 6" barrel they're moving nicely enough.

 

[Storm1969]

Try IMR 4227. I get my best velocities and accuracy using near max loads with a 158gr SWC.