nksmfamjp
Member
I’m a bit confused. SAAMI bore and groove diameters are the same. It is not clear to me why the bullets are not the same. I would try them in a 38/357.
Thanks for all the replies. I think I'll wait and get some 357 bullets.
For the 357 Magnum specifically I use the LEE Factory Collet Crimp die. This takes care of the cannelure issue and holds any projectile firmlyLee factory crimp die might make it happen
To overcome the neck tension problem ... See post #12 .My concern would be neck tension on the smaller .355" bullet.
Typical factory expander buttons are 3/1000th's smaller than the bullet diameter the calibers designed for. Hence the 357mag ='s a .354" expander button.
.354" expander/.355" bullet, not ideal for neck tension. Words like bullet setback and jump will start entering the vocabulary.
The smaller diameter bullet is meaningless in the bbl's. Too small of a bullet and the worst thing that could happen is the bullet tumbles.
I've never measured the older Colt .38 or .357 Magnum bores, but as you mentioned, they are considerably tighter than S&Ws which are usually around .357". .355" sounds right for an average for the Colts, but I believe it was gunwriter Ken Waters who stated in an article that some of the Colt barrels were as tight as .354". Regardless, I use cast bullets of .3575" to .358" in all .38 Special and .357 Magnum revolvers. They work fine and are accurate. .355" 9mm bullets would probably work well in the older Colts.
I wound up with some Super Vel 110 grain .38 / .357 jacketed bullets years ago. Super Vel sold component bullets but I don't know how popular they were. I don't recall the diameter but they were noticeably undersize for .38 caliber. To use them I would have had to change the adjustments on my dies which I chose not to do for a partial box of bullets. Undersize bullets may lower pressure but I'm not sure they would do much for accuracy.
Super Vel used smaller diameter bullets to get the higher velocity they wanted.
I did some load development work on another board with 147gr Speer Gold Dot G2 bullets in 38 Special +P. The thread started by another poster was intending to re-create the Federal 38 Special +P+ 147gr Hydrashock FBI load from I believe the '90's.
It used a 147gr 9mm Hydrashock bullet at about 1kfps from a 4" barrel. With the Speer G2's (from American Reloading) I was able to get 1k fps with a healthy dose of HS-6 (at +P pressures per GRT) and ended up using a Lee FCD to keep the bullets from moving. They shot just fine out of three different revolvers.
The other poster loaded up some in 357 Magnum with a max charge of HP-38 and got over 1100fps out of a 2.75" M66.