Commerical Cast Range Report, AKA "The Blue Lube Blues"

[nody]

Ran a series of 12 round groups today with Bulletworks of Breckenridge, TX.

Load was Alliant 2400 (fresh) 12.0 gr - 15.0/ 0.5 increments, 158 gr SWC, Starline virgin .357 Mag brass, Winchester STD primers.

Temp 39*F, light mist, no wind, 30 YARDS (not feet), S&W 586-(none), 6" bbl, open sights (partridge front), nailed/stacked 2x4/2x6 rest with towel pad--zero movement, zero flinch.

Bore scrubbed every 12 rounds. Cylinder exterior wiped to check for soot buildup. Testing for pressure signs, leading, accuracy. Don't have a chrono, unfortunately.

Questions/comments/observations…please chime in:

1. Is that roll crimp sufficient?

2. Notice as the pressure goes up, the cases generally get cleaner, especially around the case head groove.

3. 15.0 grs was the only load that kept all 12 on the paper.

4. Does primer flattening seem excessive at 14.5 to 15.0? All cases looked fine, slipped out of chambers with gravity.

5. Don't have a micrometer, but with digital caliper, bullets measured .355-.357 out of the box!! Don't think I'll be buying these again, though I'd like to mic them. I'm guessing this is the cause of the poor accuracy?

I have NOT slugged my bbl…again don't have a mic, and with 5 groves I'd be hard pressed. I have asked a few gunsmiths about slugging my bbl, and gotten an "are you stupid?" look.

6. Range notes show unburned powder at each level, lots of soot on exterior until 14.5 gr, though decreasing with pressure, no leading at 12.0-13.0, 13.5 leaded somewhat 1" from throat, 14.0 leaded same + 1" from muzzle on one grove (different groove than throat end), 14.5 minor lead at same 1" from throat area, 15.0 no leading, gun exterior cleaner.


https://lh3.googleusercontent.com/-u4SttY9SVBM/TznLMjOjmiI/AAAAAAAAANY/XQUjdK9sQQk/s640/IMG_0950.JPG
https://lh4.googleusercontent.com/-ca2_TxARLW0/TznLQ9hr6iI/AAAAAAAAAOQ/GS8JgOhxJWs/s640/IMG_0962.JPG
https://lh6.googleusercontent.com/-0Uihhta9tVU/TznLRmrahaI/AAAAAAAAAOY/wdYfYn1jwxg/s640/IMG_0963.JPG
https://lh3.googleusercontent.com/-xDjw4tUQ0BU/TznLUUqoulI/AAAAAAAAAPA/_S6oP0J7LC4/s640/IMG_0970.JPG
https://lh5.googleusercontent.com/-o1BrS09jukQ/TznLUsc5YVI/AAAAAAAAAPI/AyEes_zPxXY/s640/IMG_0971.JPG
https://lh6.googleusercontent.com/-_ML2gsRUHpc/TznLVSv3STI/AAAAAAAAAPQ/9mMXrhu5TnQ/s640/IMG_0972.JPG
B/C targets are 7.5" in diameter to outermost ring
https://lh6.googleusercontent.com/-6gf9biHQZeA/TznLXOvQhXI/AAAAAAAAAPc/t21sP2DjXx4/s640/IMG_0976.jpg
https://lh4.googleusercontent.com/-Eh-fLnh3xFU/TznLW2UbH_I/AAAAAAAAAPY/tuk2iEE3AtU/s640/IMG_0977.jpg
https://lh3.googleusercontent.com/-mnaIXaTu4yw/TznLXz469SI/AAAAAAAAAPo/wBf5ZznXZB0/s640/IMG_0978.jpg

13.5 grs
https://lh6.googleusercontent.com/-K-xrzLjQePM/TznLYutSjcI/AAAAAAAAAPw/cf9dM2Oxf-A/s640/IMG_0979.jpg

[nody]

The rest of the pictures.

For these three I switched from a 6:00 hold on the red (white @ 13.5) bullseye, to 6:00 on the black, to pull the groups down. No sight adjustments were made.

https://lh5.googleusercontent.com/-6wpa3Ulx7w8/TznLaCcv6FI/AAAAAAAAAP4/uq0hOUDeA4g/s640/IMG_0980.jpg
https://lh5.googleusercontent.com/-uVTOv-w6QPw/TznLbJOrmsI/AAAAAAAAAQA/tzlevyfjZEw/s640/IMG_0981.jpg
https://lh6.googleusercontent.com/-Fepo1QEtHvc/TznLbX3X2ZI/AAAAAAAAAQE/Y6uQGUJDuto/s640/IMG_0982.jpg

[canyon-ghost]

I'm calling 13.0 grains, seems the most consistent group. That's my eyes on it. With 2400, I'm running 15.5 grains in a 41 magnum. My heavyweight 220 grain runs 15.7 (gleaned from a TC Contender load for 41 mag).

That 13.0 target looks best to me. Your crimp is a tad tight but, it is roll crimp rather than taper crimp. That may be the difference in looks.

[canyon-ghost]

Looks like at 13 grains, your pressure is up and the cases are cleaner. 14.5 shows a spread like a shotgun- accuracy already left. 15.0 is all over the target too.

I've found that my Blackhawks usually shoot the first good group that goes just left of center. No, I have no idea what the location has to do with it but, it's always the load that corrects for me.

[canyon-ghost]

As a source for strong action loads, I use LoadBooks USA TC Contender manuals. It shows 13 grains to 14 grains for 357 magnum. Also shows 357 Maximum loads with lead being 15.0 thru 20 grains.

I'm not a advocate of ladder testing but I'd run 12.5 thru 13.5 in one tenth grain increments and see what I got.

[PacMan]

Go ahead and slug your barrel and then see if the slug will slip thru the cylinder throats and you are half way there. Get you a Mic. and slug your barrel.Contary to what some say it is not that hard to get a usefull reading by slowly turning the bullet between your fingers and slowly/gentely adjusting the mic. finding the two high corners.
But you will also need to slug your cylinder throats.

[Larry Gibson]

Quite frankly I think those are poor bullets and that is the result for the poor accuracy. The crimp is fine but the front driving band is very poorly filled out and if the measured size varies that much then that is the accuracy problem. Hard to actually tell but I can see what appears to be some evidence of bullet yaw in the bullet holes. You should be using quality bullets of .358- .360 preferably. With 2400 14 - 15 gr has always been a very good and accurate load with 150 160 gr quality cast bullets for me over 40+ years. Suggest you switch bullets to a 150 - 158 gr cast bullet (a flat based will be better than a bevel based one, especially if the bevel is large) and test again with 14 - 15 gr 2400.

Larry Gibson

[Echo]

+1 for Larry. 15 grs of 2400 has been my go-to load for the 357 for many years. I see no issue with the primers. And I see NO groups worth calling a group. Try pouring yourself a hot one and make your own! Three fifty six indeed...

[excess650]

I would suggest cleaning your barrel throughly and pusing a soft lead slug through. See if this same slug will slide through the cylinder throats or not. If not, the groove diameter is larger than the cylinder throats and NOT a good situation. This would require reamint the throats to be larger than the groove diameter. Too, while pushing the slug through, check for loose and tight spots. If its noticeably tighter at the barrel threads, its part of your problem (as would be loose spots).

Wrap your barrel slug in known thickness shim stock and measure, and then subtract (2) thicknesses of the shim stock.

I suspect your store bought boolits are undersize for you revolver in addition to being less than nicely cast.

[TXGunNut]

Big surprise, nody, I'm going to recommend you gear up and cast your own. I'm betting we've all tried store bought cast bullets and decided we could do better, I'm also betting you can too. I'm not saying you can't buy decent cast bullets, I'm saying you can cast great boolits if you hang around here and do a bit of reading.
Gotta warn you, it can be a fascinating endeavor.

[nody]

Thanks Gents!

I intend to follow the getting into casting advise at the earliest opportunity. In the meantime I have heard decent things about Missouri Bullets. Curious to hear your thoughts.

I will get the mic and slug the bbl and throats; I'm very curious to see the outcome.

Agreed those "groups" are more like shotgun patterns. :(

Grateful for your replies.

n.

[Gunnut 45/454]

Yep agreed - them bullets should no less then .358" thats what I size my 357 mags too. At 30 yards rested you should be getting a nice group of 2" or so. I know my 357 Mag BH will.[smilie=l:

[popper]

Shot ~1K MBC .40 SA with decent accuracy, no leading or feeding problems. 9mm is OK too, once you find the right OAL.

[leadman]

I agree with Larry on the poor quality of the boolit in the picture. Size is probably tooo small also.
Since you are developing the loads in cold temps use caution when the temps are up in the summer.

Most calipers are accurate enough for checking bore, cylinder dimensions. Remember you are using the same instrument for all of the measuring so if it is off it will be off the same amount for all the measurements you make. The actual measured size is not as important as the relationship between what you are measuring in a revolver.
You want the cylinder throats to be larger than the barrel. Doesn't matter if the throats are .359" or .360" as long as they are close to the same for all, and they are for best results .001" or .002" larger than the barrel.

[nody]

As a follow up, I took your advice as far as a new bullet manufacturer, and the results were telling. Thanks again.


A good bullet, the Missouri Bullet Co 18 BHN, 158 gr. SWC

http://www.missouribullet.com/results.php?category=5&secondary=10

is pictured left, and a poor one, Bulletworks, right:

https://lh6.googleusercontent.com/-G1K1QZxLXQM/T2F-SxB5EDI/AAAAAAAAAlU/84anfD9bmhg/s640/IMG_1012.JPG


The MO was the proper size, .3585 by my micrometer. The BW mic'd at .3565, which is too small. Notice also the shoulder is poorly cast on the BW, but square on the MO.


Pathetic accuracy off a rest (human frailty removed) with BW:
https://lh6.googleusercontent.com/-K-xrzLjQePM/TznLYutSjcI/AAAAAAAAAPw/cf9dM2Oxf-A/s640/IMG_0979.jpg

Now the same load with a Missouri Bullet Company 158 SWC:
https://lh3.googleusercontent.com/-r9jryycCiHc/T3XvnPfdqlI/AAAAAAAAAxI/8R2mgt1r8nc/s640/IMG_1033.JPG

[leftiye]

Go to a R/f design. Get somebody to sell you some good cast boolits to test. Slug your barrel. Make your chamber mouths a thousandth bigger than your barrel's groove diameter. Size your boolits at chamber mouth size or better still a half a thou bigger. Then if the classic 14 to 15 grains of 2400 won't shoot then you've got a problem. Try some Blue dot about 10 to 12 grains.

At least you've identified that those gunsmiths don't have a clue. Nice Starrett micrometers can be had cheap (and used) on eVil bAy. Slug your barrel, measure with your cailpers. (hint: the trick is to measure everything with the same instrument) Five groove rifling can be accurately measured with a micrometer or calipers. The leading edge of one land is diametrically opposite the trailing edge of the opposite land when lands and grooves are the same width.

[nody]

Try some Blue dot about 10 to 12 grains.]

https://lh3.googleusercontent.com/-u0lDCZ7_XPo/T2FebjqbyYI/AAAAAAAAAiw/qHEKSj4n2X4/s640/IMG_1025.JPG9

https://lh4.googleusercontent.com/-CBwju32cf4Q/T2FegYMh6LI/AAAAAAAAAi4/1Cfa84Cec8Q/s640/IMG_1028.JPG

[runfiverun]

i wouldn't be too impressed with the missouri one either.
they seem to be shooting fine, but that drive band you picture would go back in my pot.
i am not that good with a revolver i need all the help i can get.

[41mag]

You might contact Dry Creek Bullet Works as well and see if he might send you a sample pack of 25 or 50 boolits to try out.

From what I have seen and read he pours some very high quality boolits in several calibers not listed on his site, and his prices are pretty decent as well.

Least worth the time of an email.

[nanuk]

perhaps some of our Sponsors have what you need, if you are not going to cast your own

Just sayin'

[popper]

Or Carolina bullets(sponsor). He has TL .356 SWC, might size them larger for you if needed. His .311 30-30 are good quality.

[bogman]

Try Rimrock bullets, or SNS casting, both work great in my S&W #586 & my Ruger #77/.357