I could use a little advice, opinions, thoughts with my .357 magnum loads

[WebMonkey]

hello all.

this is my first endeavor to work up a hunting suitable load for a .357 magnum handgun.

I'm having issues with reaching (perceived) pressure ceiling before a decent velocity is attained.

platform:
ruger Blackhawk stainless convertible 6.5"
R-P nickel cases
LEE single cavity swc hp dropping 137.5gn (50/50 alloy) powder coated with smoke's blue+silver
unique and 2400 powder
Winchester small pistol primers
Lee auto disk powder measure checked against lee unbreakable scale and pocket digital scale
lyman cast manual, lyman 48th, alliant manual, etc.

anticipated target distance: 25 yards or LESS




sorry for the blurred photo


so, flattening of primers is what I'm getting even though the pictures don't tell the story.
unique data:
Created: 09-29-2016 01:35:14 PM
Description: lee 137gn hp .357 magnum
Notes 1: 7.1gn unique
Notes 2: blackhawk 6.5"
Distance to Chrono (FT): 15.00
Ballistic Coefficient: 0.117
Bullet Weight (gr): 137.500
Altitude (FT): 0.0
Temp: 69 °F
BP: 30.25 inHG
Shots
# FPS FT-LBS PF
5 1253 479.42 172.29
4 1250 477.13 171.88
3 1283 502.66 176.41
2 1248 475.61 171.60
1 1233 464.24 169.54
Average: 1253.40
StdDev: 18.26
Min: 1233
Max: 1283
Spread: 50
True MV: 1271.76
Shots/sec: 0.25

so for UNIQUE, I get close to the speed I think I need when I start getting a flattened looking primer.
maybe 1 in 5

now 2400:

Created: 10-01-2016 01:47:22 PM
Description: lee 137gn hp .357 magnum
Notes 1: 15.2gn 2400
Notes 2: blackhawk 6.5"
Distance to Chrono (FT): 15.00
Ballistic Coefficient: 0.117
Bullet Weight (gr): 137.500
Altitude (FT): 0.0
Temp: 66 °F
BP: 30.06 inHG
Shots
# FPS FT-LBS PF
5 1343 550.77 184.66
4 1388 588.30 190.85
3 1412 608.82 194.15
2 1364 568.13 187.55
1 1405 602.80 193.19
Average: 1382.40
StdDev: 28.76
Min: 1343
Max: 1412
Spread: 69
True MV: 1402.65
Shots/sec: 0.50

I'm makin' gravy now but flattened primers are 4 out of 5

obviously I could just back down the 2400 but I'd rather use the unique as it is far less powder usage.
I just can't get unique OR 2400 to replicate what the manual says I should get for the charge before primers are flattening.

any advice, comments, thoughts on unique in the .357 magnum for hunting would be appreciated.

[dadeo316]

I get flattened primers with factory ammo.

Sent from my LG-H811 using Tapatalk

[shoot-n-lead]

Since your distance is short, I would back off until the primers look suitable to me...and live with that fps. As close as you will be, it will make little difference in bullet performance. IF...I were concerned with penetration...I would go to a heavier bullet. Just me, but I won't use any bullet that light for deer...at any range. If I am small game hunting, I have no use for a hollow point...solids are deadly on small game and not destructive.

[WebMonkey]

^ figured that would probably be the case.

i need to invest in another mold. i would get an noe if it were in stock, but it's not (tumble lubed/checked 175gn round flat).
i'll probably go with the lee c358-158 swc in a 6 cavity.

the hollow point i cast now is lighter than i'd like for the purpose but already used it for 38spl snubbie loads (which the lighter projectile is nice).

thanks!

[osteodoc08]

The pictures that I can see and evaluate on my iPhone look fine to me. Your primers are brass colored meaning Tula, Winchester or Remington brand primers most likely. The Winchester and Remington are softer cupped compared to say CCI. Federal are pretty soft and will show signs of flattening before a harder cupped primer like CCI.

If you want max velocity, look to 296.

What are you hunting? If a deer or smaller, your 2400 loads are more than enough. Place the boolit in the vitals and you'll be successful.

[DougGuy]

See if you can push your coated boolits through the cylinder throats. They should go with finger pressure. If they won't go without being forced, this could raise your pressures quite a bit especially if you are near max already. The gun will likely stand up to this over pressure event as long as you own it without issue or damage. It's Ruger, it's what they do, but check the throats.

I would back off the 2400 and be happy with 1200 ~ 1250fps which is plenty enough velocity that you probably won't recover a boolit, and terminally I doubt 100fps will make any difference in how dead the deer is because afterall, shot placement is KEY and if you have hit the boiler room in the right spot, 800fps will kill the deer just as dead.

If you discover you need a cylinder reamed, turnaround time is really quick so you'd be back at it in less than a week.

With 50/50+2% in the pot you wouldn't ever need a HP to hunt with so you could pick up some weight right there, I would be hunting with a heavier RF boolit that I can scratch with a thumbnail were it me.

[reddog81]

It could just be that I'm looking through the small screen of an iPhone but I don't see flattened primers. Google "flattened primers" and look at the images where the primer expands to fill the whole primer pocket. On a flattened primer the edges of the primer aren't rounded, they are sharp and pushed up to the edge.

Maybe your primers are starting toward being flattened and if so it maybe be prudent to back off a little

[pietro]

.

Switch to a 158gr boolit/mold.... +1


.

[44man]

Flat primers are not an indication. They back out some and the case slams back to seat them again. Depends on head space. Normal loads can have flat primers.
You don't need the velocity you expect, throw the books out.

[Walkingwolf]

Switch to magnum primers which are harder. Magnum primers can be used on any load even light loads, the only problem with them if the firearm has a weak primer strike.

[Bazoo]

Flat primers in a 357 blackhawk is not uncommon in my experience with either reloads or factory ammo.

One upon a time, i worked up a load using the ideal 358156 gas checked and 15 grains of 2400 with a CCI 550. It did have flat primers, but extraction was okay if I recall correctly. Thats one of the classic loads. I didnt have a chrono at the time, the book said 1450fps or so however.

+1 on using magnum primers.

[SciFiJim]

A couple of suggested magnum primers. I was going to suggest small rifle primers for the same reason. Your pistol should have no problem with the extra striking force needed to ignite them. Of course, back down the load and work back up to test your loads.

[WebMonkey]

***************
thanks everyone.
from all the suggestions:

i'm going to get a new mold of the 158gn weight and work up to 1250fps.

not fret about my cases/primers as the spent cases all would fall out of the cylinder just from gravity and the flattening was not as pronounced as i feared.

drive on and put some meat in the freezer.

thanks again for all the input!

[osteodoc08]

Be cautious with rifle primers. They are taller (0.005" or so) and if they are not below the case head, can slam against the recoil shield and ignite. Even Freedom Arms has a warning about this on their website. There are very few revolver cartridges that call for rifle primers and are designed for their use. 357 Mag isn't one of them.

From FA website regarding the 454 Casull which does recommend rifle primers:

Magnum primers perform more reliably at temperatures below zero degrees F.. Magnum primers will most often give more uniform velocities in magnum pistol loads using slow powders, and heavy bullets. More importantly the heavier construction of the primer cup prevents metal flow back, and provides a more positive ignition. Remember to always seat the primer below the case head to prevent recoil from firing the cartridge while not aligned with the barrel.

[Thumbcocker]

don't get hung up on speed. I would like a heavier boolit. A 160 rnfp at 1250 or so would be peachy. 2 holes dead critter.

[Blackwater]

I've shot a couple of tons of that bullet in my .357's I've had, and it has worked well on everything I've shot with it. A buddy killed two deer with it, one in .357 and the other from a .38. I've shot both the loads you're using, except back then I often used 8 gr. of Unique, and never had a problem with brass life or anything. That was in a Ruger and a S&W M-19. Don't believe I ever went to 15 gr. on the 2400, but was so satisfied with the Unique, I never shot many. Topped out in my experiments at 14 gr., and I think I tried some at 15, but settled on the Unique for much the same reasons as you have.

The flat primers are a characteristic of max. to warmish loads, and not an indication of excessively high pressure. As well as I can see in your pics, I don't see any sign of excessive pressures. I think you're good to go, from what you've posted and what I can see on the pics you've posted. I always used a lube rather than PC, which wasn't even around back then, but that shouldn't make any difference, I don't believe.

One last thing, as Doug said, I'd use a softer alloy to let that HP do its work, and tin, at least 2% and up to 6%, helps keep the bullet's malleability, and keeps it from breaking and splintering off on impact. But even with straight ACWW's, it always did a good job, even on our smallish Southern whitetails. It's more about where you put a bullet than what bullet it is, providing only that it reach the vitals. That's been my experience, but I snipe them, and I can't remember any who were even aware anyone was in the woods, much less aiming at them, so that has to be taken into consideration too. As with so many things, killing deer is pretty much in the details, more than anything else. Looks to me like you're doing a fine job!

[farmbif]

I have had oustanding results with alliant 300 mp in 357 125 gr - 158gr and 44 200 gr-270gr in both cast and jacketed bullets. I think you will be pleased with results from this powder very close to if not better than lil gun velocity without possibility of barrel damage. You don't necessarily need the hottest possible load to kill an animal. Bullet placement is more crutial.

[telebasher]

I, too have a 6 1/2 Blackhawk and have shot thousands through it chasing "the load". That all ceased when I got a 358429 mould and settled on 12 gr 2400 as "the load". Easy to shoot and that boolit will penetrate deer, coyotes etc. like no other I have ever tried. This summer I have been playing with HS-6 and from what I've seen so far, me likey, me likey a lot. Just might have found another load. Need to shoot more past 50 yards to compare with the 2400 load.

[country gent]

For a hunting load I would be more concerned with pin point accuraccy over velocity. A suitably heavy bullet for energy retention and penetration is a big plus also. With a good bullet desighn wfp or even a semiwad cutter the energy transfer should be fine. The few deer Ive taken with 357 were basically a 160 grn semi wadcutter at just above 38 spl +P velocities. A solid hit and none traveled more than a few feet. Bullet placement is much more important. Nothing will make a poor shoot a good one. Work up a good accurate load with a 150 -180 grn bullet and place the shot accuratly.

[MT Gianni]

Be cautious with rifle primers. They are taller (0.005" or so) and if they are not below the case head, can slam against the recoil shield and ignite. Even Freedom Arms has a warning about this on their website. There are very few revolver cartridges that call for rifle primers and are designed for their use. 357 Mag isn't one of them.

From FA website regarding the 454 Casull which does recommend rifle primers:

Magnum primers perform more reliably at temperatures below zero degrees F.. Magnum primers will most often give more uniform velocities in magnum pistol loads using slow powders, and heavy bullets. More importantly the heavier construction of the primer cup prevents metal flow back, and provides a more positive ignition. Remember to always seat the primer below the case head to prevent recoil from firing the cartridge while not aligned with the barrel.

LR primers are taller than LP primers. SR and SP are the same height.