Help with 9mm

[walker77]

Im getting ready to start casting for my 9mm sig P6. I am still new to casting, ive been casting for revolvers, and im about to the point to get that figured out. Although, im still gettting a little leading. But anyway, this is my first attempt at casting for a semi auto. I slugged the barrel and its at .355 So what size of sizing die do you guys think i should go with? I have a .358 for my 38spl, any chance of getting away with sizing that big? Thanks guys

[RobS]

Whether it is right or wrong or as to one way or another, the standard is .001-.002 over groove diameter, although I will size to whatever will reliably feed in my autos. I've been able to go .002 over on all that I have loaded for and can even squeak by with .003 in a 45 auto. Start on the minimum side of the powder charge weights in the manuals and if .003 chambers for you then it is an option. If you have a tight chamber then you will have to work at a smaller sizing diameter. Through my experiences the larger diameter bullets seems to, in most situations, work better regarding accuracy and it also helps reduce leading in my guns.

[helg]

Common wisdom that bullet can be sized down to .006". You should be OK sizing the bullets to .356" to match your .355" barrel. Be aware that not all revolver bullet shapes are good for 9mm loads. WC is an example.

[walker77]

I bought a lyman round nose 9mm mold to make sure i dont have any feeding issues.

[454PB]

In my opinion, use the largest size boolit that will chamber freely.

I have five 9mms, and size all the boolits .358". My Rugers have .356" bores, and eat the .358" boolits just fine.

[walker77]

what did your barrels slug at?

[RobS]

His barrel is .356



what did your barrels slug at?


In my opinion, use the largest size boolit that will chamber freely.

I have five 9mms, and size all the boolits .358". My Rugers have .356" bores, and eat the .358" boolits just fine.

[Ole]

My SW59 likes the Lee 125 grain 358RNFP sized to .357"

No feeding or leading issues at all.

[Echo]

In my opinion, use the largest size boolit that will chamber freely.

I have five 9mms, and size all the boolits .358". My Rugers have .356" bores, and eat the .358" boolits just fine.

+1 - I believe in loading the fattest boolits that will chamber, in autos.

[GabbyM]

I'd just try the .358" die then see how bullets work. May save the cost of a new die plus the hassle of swapping dies. Your Lyman mould may not drop a .358" bullet.

.357" is my standard 9mm size and you are literally splitting hairs between .357" and .358". Most NATO chambers are cut to combat specs so theirs plenty of room to grow your bullet.

Nice to hear SIG actually puts out a barrel within spec. Always admired those pistols but for some reason have never fired one.

[walker77]

I really like my P6 ( P225 ) My wife got it for me a year ago when they were still under 300 for them. Its just a single stack, but for a range gun, who cares? It fits my hand great. Ill see how this works out. If everything goes good, ill try casting for my P220. I dont really shoot it much, its been hard to find 45acp. But i hate to get rid of it. Both my P6 and my P220 is marked West Germany.

[RobS]

If everything goes good, ill try casting for my P220. I dont really shoot it much, its been hard to find 45acp. But i hate to get rid of it. Both my P6 and my P220 is marked West Germany.

If you continue to plan on casting, definately do not get rid of the 45 ACP as it is the easiest cartridge to shoot cast from out of all the other auto's. The lower pressures make it so very easy to shoot a cast bullet and just about any shotgun powder will work well in the round. It is really difficult to find a load that won't work well in the 45 auto where as the 9MM is much more difficult IMO. You are a Sig man and they are a great firearms company. Keep us posted and we will all chime in on our experiences to help you out.

[putteral]

I also have a P6, P228 and a P220R. I slugged my P6 and it came out to .3555. I tried a Lee 124TL-TC and 105 gr SWC sized at .357 with the Oal at 1.07. Would not chamber reliably. So I stick with sizing to .356 and same OAL and do not have any problems. All my sigs are very accurate with any lead projectile I use.

[walker77]

Any problems with leading with them? Is there any different steps i need to take to prevent leading?

[putteral]

I get very little if any leading . I do water quench. My P6 and 228 like 5.6 grs of AA #5 over the 124 TL-TC. For the 105 gr 4.3 grs of Titegroup have worked the best for me. The 220 never leads with 4.7grs of Titegroup over any 200gr lead boolit. ( Lee SWC,RNFP&Mihec's HP) Most accurate of any of my 45's