Bullseye Load Data - 158 gr SWC 357 Mag Mid Range

[Hi-Speed]

I have Lyman data using 358311 and 358156 bullets with Bullseye. Some charges range up to 7.0 grs Bullseye (36.5k cup)…which seems high to me. Lyman uses CCI 550 magnum primers in all their 357 Mag loads including Bullseye. I also now use CCI 550 in all my 357 Mag loads even mid range (my rationale: the faster burning powders take up less space in that long cartridge and I want to ensure a consistent burn with them by using magnum primers.)

Does anyone have actual Bullseye 357 Mag Mid Range chronograph data? I’m looking for a load at approximately 1,000 fps with 155-160 gr SWCs using Bullseye.

For 38 Spl +P I have Lyman data which allows use of 4.0 grs Bullseye with 155-160 gr bullets…that’s another load development. Seems like a good standard +P load (4.0 grs BE/158 gr SWC).

[quilbilly]

I have enjoyed for many years using 4.6 gr of Bullseye in my 357 revolver with the cast Lee 125 gr RNFP (drops for me at 132 gr) giving an MV of about 960 +/- 20 fps. It has been very accurate, useful, and fun to shoot. I don't use my 165's very much in the revolver but regularly in a 357m bolt rifle. I would imagine in a revolver, the 165's would have an MV of about 920 fps with that same 4.6 BE load. I am not using magnum primers in the pistol but use small rifle primers in the rifle.

[Dom]

158's in a revolver. Target load 2.7 to 3grs. I have used this load for 50+ years. Super mild & super safe in my revolvers.

[ABJ]

I do not have chrno data, but went to Alliant site: "158 speer lswc, cci-500, Bullseye, 4.8 grains is 939 fps."
This is as much Bullseye or anything else in that range as I would want to use in a 357 case. They get a little snappy.
My accuracy round is in the 4.5/4.6 for a 158/357 case using Bullseye. If I want more I move to Unique and true magnums I use Blue Dot, then 2400 or 4227.
Let us know how your test loads preform.
Tony

[30calflash]

I think the use of Mag primers in some manuals is for testing extreme loads as there's nothing to be gained by their use with most Alliant or Hercules powders. If pushing loads hard then the mag primers may be a safety when loads get 'up there'.

I think the load you're looking for is safe in 357 but may not perform the best at that velocity, only a test will tell.

IIRC Bob Hagel did some high load testing w bullseye in snub revolvers, for better velocity and not lighting up the neighborhood.

Loads are listed in the powder guide for pressure only, not accuracy.

[Low Budget Shooter]

From 6" barrel Model 19-3

case: misc 38 Special
bullet: 358311 165 grains
charge: 3.5 grains Bullseye
primer: Federal
velocity: low 753 high 813 avg 781

case: Federal 357 Magnum
bullet: 358311 165 grains
charge: 6.5 gr Bullseye
primer: Federal
velocity session one: low 973 high 1036 avg 1015
velocity session two: low 1028 high 1065 avg 1049
accuracy at ranges from 7 yards to 200 yards was excellent, among the best I've seen
CAUTION: I was using a custom oversize +.003 Lee case sizing/decapping die, so pressure was less than it would be with standard case sizing/decapping die.

case: Federal 357 Magnum
bullet: cast 155 gr SWC
charge: 5.5 gr Bullseye
primer: Federal
velocity at 70 degrees: avg 1025
accuracy good even at 200 yards

case: Federal 357 Magnum
bullet: cast 155 gr SWC
charge: 6.0 gr Bullseye
primer: Federal
velocity at 70 degrees: avg 1084
standard sizing die

case: Federal 357 Magnum
bullet: cast 155 gr SWC
charge: 6.5 gr Bullseye
primer: Federal
velocity at 70 degrees: avg 1142
standard sizing die

[Hi-Speed]

Thank you all! Good information

[rintinglen]

A load that I have used is the 358-156 loaded short and 5.5 grains of Bullseye with Winchester small pistol primers and giving about 1025 FPS. from a 6" Security Six.

Unfortunately, I can't say if those were estimated or measured velocities, as all I have is a penciled note in an old Lyman to go by. I got a Shooting Chrony in the early 90's and I may have run them through it then. But I don't use my BE for that any more and for most of the last 25 years I have used WW231/HP38 for those purposes.

[Forrest r]

I've used 5.5gr and 6.0gr of bullseye and any +/- 160gr cast bullet for decades as a plinking load in the 357mags.

Typical 6-shot groups @50yds from a s&w 686
https://i.imgur.com/CfpwHXk.jpg

[Rodfac]

With Lyman's 358156 GC bullet, cast from ACWW + 1% tin and sized to 0.358" with an annealed Hornady GC; 5.5 grains of current production Bullseye gives me 996 fps from my 1980 vintage Smith M-66. This is a sub-2" grouping load at 25 yds from a rested position. It's equally good in a 1985 vintage S&W M-19 and a M-686 of the same year group. All three are 4" bbl'd guns.

Notes: Starline .357 Magnum brass and Winchester Sm Pistol primers used with all loads. With 6.2 gr of WSF, or 6.9 gr of Herco, I've chrono'd right at 1000 fps from my 4" K frame Smiths. Without the GC, 6.0 gr of Unique gave me 1034 fps and ES of 27 fps...this Unique load gave me my best accuracy of 1-1/2" @ 25 yds, BTW, and with no leading whatsoever.

The annealed gas checks seems to give better accuracy than ones that haven't been annealed. I anneal by placing a handful of GC's in a stainless steel bowl and heat them cherry red with a Berns-O-Matic torch.

I use as little crimping as possible; only enough to prevent bullet jump in recoil. At this level, a taper crimp works well and gives a bit better accuracy.

Reducing the powder charge to 5.3 - 5.3 gr. of Bullseye will give you 4" bbl. velocities that duplicate the old 'FBI' load of ~950 fps with a HP LSWC.

HTH's Rod