41 cal jacket, size up or down?

[BT Sniper]

Hey guys,

Going to make a lot of 41 cal bullets and I have tried the 40 S&W for a jacket. Works good but a little tough to size down.

Any ideas on bumping up a 9mm for a jacket?

Generialy which is prefered size up or down for a jacket? The spring back from the 40 S&W is giving me some difficulties as I don't have a sizing die smaller then .410 yet.

Thanks

BT

[BT Sniper]

May have answered my own question here as the 9mm worked great for a 410 jacket.

[BT Sniper]

Here is a pick of the two. Both weight 218 grains. The one on the left is from an unaltered 9mm and the one on the right is from a 40 S&W case cut down to .65 long and pushed threw a sizing die. The 9mm version was certainly easier.

Notice the 9mm version is shorter and has less grove yet still same weight. I like that.

Good shooting

BT

[scrapcan]

BT

How did you go about using the 9mm? did you expand first then seat core? Or did you do the core seat and expand all in one motion? I pm'd another member about this topic and he said he used 9mm also. I would have to look up the pm to give the correct member.

[scrapcan]

BT the other member was Wonderwolf.

[BT Sniper]

All I did was bell the 9mm case mouth to accept my core. If the core was a bit smaller in dia I would not of even had to do that. Then it was a good squish in the core seat die and all is well. Rim comes out at about .405 unless you really put some fore to it but the rest of the jacket/bullet is right on .410. With out the propper sizing die to bring the 40 S&W brass down to a size less then .410 it is a bit of a challenge to use the 40 brass.

[BT Sniper]

Care to post a link?

[scrapcan]

BT,

below is the message I recieved via email. I had sent an pm based on a posting, but did not save the post.


This is the message:

there are some who have done a lot more on this than I have but so far what I've learned is you have to make sure to anneal your cases. make sure you have enough extra lead so that when you seat the core the case bumps out to fill the entire die. 40 caliber bullet is more ideal for 9mm cases but 41 can be done with some fine tuning. Are you using 101 dies? or 105? The lead core must be as pure lead as you can get and if you are casting your cores try and find something around a 357 bullet that has as few crimp/lube grooves at all as the case/bullet jacket will fold on you. I have been messing with a mold I found in my friends box of molds that is a paper patch mold for a .375 caliber gun. The core is a little short but my results have been fairly good so far. Since the core is a little shorter than it should be it is not being seated all the way in the case so the case is not filling out all the way. I hope I've helped out some.

[Grapeshot]

I tries using 9mm berdan primed brass for .45 cal bullets. They work, but they would be better in making .41 or .40 cal bullets.

[Cannoneer]

I have a box of .401 half jackets you can use for your .41's

contact me at canoneer74@hotmail.com

[wonderwolf]

I had to flare out my case mouths as well in addition to what was posted above.

[Jim_Fleming]

Agreed, the 9 mm case looks a lot better, however I have a question about the 'rebated' rim. Do you think that'll degrade accuracy, since you very likely won't have rifling engagement at what I think would be a critical area?



Notice the 9mm version is shorter and has less grove yet still same weight. I like that.

[wonderwolf]

Agreed, the 9 mm case looks a lot better, however I have a question about the 'rebated' rim. Do you think that'll degrade accuracy, since you very likely won't have rifling engagement at what I think would be a critical area?

Doubtful, Could lathe turn it into a boat tail.....:p

[BT Sniper]

I was able to get the rim to swell out to .408-410. So far guys are getting some pretty good results from them.

[bohica2xo]

BT:

If the brass is well annealed, you can move it around quite a bit. Taking 40S&W down to .395 in one pass usually makes the rim less obvious, depending on the die of course.

When you reduced the 40 cases, what was the die dimension & which way did you send them through?

B.