Swede 45
09-17-2014, 08:34 AM
I used to shoot a soft 148gr commercial swaged HBWC and had problem with tumbling.. got the advice to go to a faster powder with less gas volume to keep the gas from "flipping the bullet" as it exits the barrel.. especially on shorter barrels! Theory was that the high peak of gas preasure would push to hard on the HB of the bullet and make it flip..?
I shoot a 4" Ruger GP100 and a 2½" S&W 686.. and the snubby was terrible with this load! Not so much with the 4" but with clear tendencies to tumble at 25 meters. Changing from Vithavouri N-340 to N-320 solved the problem in the 4" and shot great! My luck, the bullet is no longer available!
Now, my recent problem!
I have the same problem with my new load!
Ruger GP100 4"
Lee .358-148gr WC with a alloy that gives about 12BHN according to the calculator.
Sized .358 and lubed with TAC-1
2.8gr of Norma R1 (Same result with Vitha N-310 load at same vel. and accuracy)
Standard primers.
.357 cases, bullet seated flush to case, just the small "button" sticking up.
No rollcrimp, just a taper to keep the bullet in place and the cases to feed. (crimping/or longer c.o.l messes upp the accuracy on this load)
Velocity runs at about 220m/s at 3meters ( 722f/s at 9 feet)
Accuracy is great, sub 1 inch at 25meters, but about 2-3 bullets out of 10 shows slight tendency to tumble. Not completely sideways, just a slight oval strike and a smear on one side at the paper.
I get no leading in the barrel, but some in the cylinder throats..
So, any ideas from you guys what causes this and things I can do to fix it?
My own thoughts are towards too slow velocity, and that the bullet doesn´t get the "spin" enough to stabilize.. but I like the accuracy and the soft recoil.. I´ve tried stiffer loads with the R1 and Vitha N-310, but get accuracy problems then!
Softer/harder alloy?
Slower powder?
(I shoot mainly competitions, and a hit larger than 11mm (.433) from a 38spl are judged as null due to ammo malfuction.)
Swede
I shoot a 4" Ruger GP100 and a 2½" S&W 686.. and the snubby was terrible with this load! Not so much with the 4" but with clear tendencies to tumble at 25 meters. Changing from Vithavouri N-340 to N-320 solved the problem in the 4" and shot great! My luck, the bullet is no longer available!
Now, my recent problem!
I have the same problem with my new load!
Ruger GP100 4"
Lee .358-148gr WC with a alloy that gives about 12BHN according to the calculator.
Sized .358 and lubed with TAC-1
2.8gr of Norma R1 (Same result with Vitha N-310 load at same vel. and accuracy)
Standard primers.
.357 cases, bullet seated flush to case, just the small "button" sticking up.
No rollcrimp, just a taper to keep the bullet in place and the cases to feed. (crimping/or longer c.o.l messes upp the accuracy on this load)
Velocity runs at about 220m/s at 3meters ( 722f/s at 9 feet)
Accuracy is great, sub 1 inch at 25meters, but about 2-3 bullets out of 10 shows slight tendency to tumble. Not completely sideways, just a slight oval strike and a smear on one side at the paper.
I get no leading in the barrel, but some in the cylinder throats..
So, any ideas from you guys what causes this and things I can do to fix it?
My own thoughts are towards too slow velocity, and that the bullet doesn´t get the "spin" enough to stabilize.. but I like the accuracy and the soft recoil.. I´ve tried stiffer loads with the R1 and Vitha N-310, but get accuracy problems then!
Softer/harder alloy?
Slower powder?
(I shoot mainly competitions, and a hit larger than 11mm (.433) from a 38spl are judged as null due to ammo malfuction.)
Swede