Accuracy - Lyman 358429 loaded short vs long

[38SPL HV]

At least from my recent experience using the Lyman 358429 in 357 Mag cases, crimping over the forward driver band edge (1.553” OAL) and using 6.0 grs of Unique gave me markedly better accuracy than using the same 6.0 grs Unqiue charge with the 358429 crimped in the bullet’s crimp groove. I’m using a new model Ruger Blackhawk 4 5/8 inch. Shooting was done bench rested at 25 yd using three inch “Shoot and See” targets.

I intend to chronograph the Unique 6.0 grs load with the 358429 crimped over the forward driver band edge next week. I believe it should break just about 1,000 FPS in my Ruger 4 5/8” BH.

Appreciate your experiences regarding velocity and accuracy differences crimping the 358429 “short” and in its crimp groove.

Thank you

 

[rockquarry]

I no longer load .357 Magnum ammo, but did for many years. I don't recall ever using Unique powder with the #358429 (or the #358439 HP version), but I did use #2400 with both bullets.

My notes indicate overall lengths of 1.59" and 1.553" with the #358429 but there is no notation regarding any difference in accuracy between the two OALs. With the HP bullet, only an OAL of 1.59" was used. As for any velocity differences with the #358429, I can't comment as I only have figures for the long OAL. My testing has always been done at 25 yards and most of my .357 Magnum numbers were derived using a 6" Model 27 that I bought new in 1975.

Unique may be a good powder for the #358429 in the .357, but my results with #2400 were satisfactory to the point I seldom tried much else with this bullet.

#358429 is certainly an accurate .357 Magnum and .38 Special bullet, but I preferred the H&G #51 at about 160 grains as my first choice in both cartridges and continue to use it in .38 Special loads.

 

[cowboy4evr]

I have loaded the 358429 bullet for yrs in 357 cases crimped in the crimp groove with 7.0grs of Unique . This was the load I used and carried for a long time in my model 19 , 4" barrel and later yrs in my 686 , 4" . It's very accurate , has plenty of power . It's a combination I wouldn't change . Regards, Paul

 

[cowboy4evr]

I only have a 2cav mold for the Lyman 358429 so it doesn't get used as much . The design that gets a lot of use is my clone of the lyman 358156 (double crimp groove , Ray Thompson design) but mine has a plain base instead of gas checked . Tom @ Accurate Molds made me 2 - 4cav molds . They weigh 160-162grs . For yrs I shot those , crimped in the lower crimp groove over 7.0grs of Unique . I recently have tried BE-86 and found that 7.5grs was another gread load / combination . Regards, Paul

 

[stansdds]

I'm wondering if seating the bullet deeper simply increased pressure, resulting in a more uniform burning of that charge of Unique. More uniform burning of powder leads to less variation in velocity and that can result in improved groups.

 

[Tim357]

Off topic a little, but try loading that bullet in .38SPL cases the way Elmer Keith designed. I'd love to see the results

 

[cowboy4evr]

Older load manuals showed that bullet , loaded in a 38spl case using 6grs of Unique . It was considered a standard " back in the day " . I have shot many of that load , accuracy was great and it had a lot of power . They were fired out of a Model 28 HP , 6" barrel . It was the only revolver I had at the time . Regards, Paul