9MM Polygonal Rifling and Cast Boolits

[Bomberman]

I have a Kahr T9 that I use for my daily carry gun and I've only shot factory J-word bullets from it. I'd really like to cast for it but I've heard that cast and polygonal rifling don't go together well. Anyone have any positive experience with cast and polygonal rifling and recommend a good mold?

Thanks in advance.

[5shotbfr]

there is a sticky up near the top of this section that will help get you going in the right direction with your karh

[bobthenailer]

i have a Kahr PM9 and a TP45 both with poly barrels , after a intinal break in with jacketed bullets i have been useing only my cast bullets for pratice for at least 500+ rounds from each with no issues or leading problems .
just shoot 25 or so and look down your barrel if its ok shoot another 25 if its still ok you should be good to go! l i usually shoot 100 to 150 rounds from either gun when i take them to a range and clean the gun when i get home.

[Bomberman]

i have a Kahr PM9 and a TP45 both with poly barrels , after a intinal break in with jacketed bullets i have been useing only my cast bullets for pratice for at least 500+ rounds from each with no issues or leading problems .
just shoot 25 or so and look down your barrel if its ok shoot another 25 if its still ok you should be good to go! l i usually shoot 100 to 150 rounds from either gun when i take them to a range and clean the gun when i get home.

What boolit are you shooting in your PM9? How much over bore are they sized to?

[fecmech]

I put about 3500 cast bullets through a K9. I used my Lee 120TC sized .356 and some commercial 147's also at .356 had no problems and excellent accuracy. When the 120's were pushed to max I got some light streak leading that did not build up( it was the same after 100 shots as 1 shot) but accuracy was excellent. The Kahr line of pistols are excellent quality IMO. I personally think the hoopla about polygonal barrels is much adieu about nothing.

[Bomberman]

I put about 3500 cast bullets through a K9. I used my Lee 120TC sized .356 and some commercial 147's also at .356 had no problems and excellent accuracy. When the 120's were pushed to max I got some light streak leading that did not build up( it was the same after 100 shots as 1 shot) but accuracy was excellent. The Kahr line of pistols are excellent quality IMO. I personally think the hoopla about polygonal barrels is much adieu about nothing.


Excellent! Thank you. I love my Kahr but don't practice with it enough due to a limited budget. This helps greatly.

[bobthenailer]

What boolit are you shooting in your PM9? How much over bore are they sized to?

From my PM9 and my other 9mms i use the Saeco #377 122gr tc sized to .357 dia with Power pistol powder ,I have found with the 9mm & 38 super that med fast to med burning speed powders gave me the absulate best accuracy in every gun such as WSF , PP & HS6 as compaired to the slightly less accurate powders in my 9MMs & supers such as BE & Tightgroup. Bullets sized to .357 and the tc & swc nose profile are the most accurate over the RN profile in my guns!

[Old Caster]

I too think people do dumb stuff like double loads, bullets that will shove back into the case, and shooting a bullet on top of a squib load and then quickly blame a polygonal barrel and lead for their problem. If shooting a 9mm, keep in mind that it is real easy to take a relatively soft cast bullet and swage it way below what you want just by pushing it in a piece of brass. Just check by pulling a bullet first. I have seen so many lead bullets shot out of Glocks at IDPA matches that I know it can be easily done and have personally shot about 500 of them out of my model 19 with no problems. Like the post above. Go slow and pay attention. -- Bill --

[bcp477]

The problem with polygonal rifling and cast bullets is that the bullets tend to skid against the rifling, especially near the muzzle. This tends to leave lead deposits at the base of the rifling. Over time, this CAN build up and act like a barrel restriction, greatly increasing pressure.

By NO means, however, will it ALWAYS occur.....or that one should never shoot cast boolits in polygonal -rifled barrels. Not at all. It simply means that it is a GOOD IDEA to err on the side of caution. That could be as simple as checking your polygonal barrels for lead buildup regularly. If none is there - no need to worry about it.

[Good Cheer]

Used the Lyman 358345 112 SWC HP in a .380 with polygonal rifling back in the 1980's. Shot like a dream. Never had a problem ever.

[ebner glocken]

Shot the Lee 124gr TC in my glock 19 many many rounds. I do clean every session. If you're worried about it run a bore snake every 50 rounds or so while at the range. BTW I've had good luck with cast in a G20 10mm with no ill results.

Ebner

[schreibwy]

Have shot cast in an H K P9s and in a Glock 36, and ha had no problems if I keep them clean

[500MAG]

I don't own any gun with a polygonal barrel, but I do carry a BoreSnake for each caliber I shoot, in my range bag. I run it thru the barrel every so often while at the range. I wonder if this might help with any worry of shooting cast thru these barrels?

[bogidu]

From my PM9 and my other 9mms i use the Saeco #377 122gr tc sized to .357 dia with Power pistol powder ,I have found with the 9mm & 38 super that med fast to med burning speed powders gave me the absulate best accuracy in every gun such as WSF , PP & HS6 as compaired to the slightly less accurate powders in my 9MMs & supers such as BE & Tightgroup. Bullets sized to .357 and the tc & swc nose profile are the most accurate over the RN profile in my guns!

Greetings. Long time lurker, first time poster. I saw that you use saeco 377 and power pistol, both of which I now have in my garage. As I'm new to reloading, how many grains of powder do you use in your recipe?