size brass shot shell

[Battis]

I have some 20 ga Magtech brass shot shells. I have to resize them to fit the 1873 Maynard. They're a little too wide. Is there any way to resize these brass shot shells without having special dies made?

[cwtebay]

What are you trying to reform to? I didn't realize that there was a Maynard cartridge that large.

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[Battis]

It's a Maynard smoothbore barrel that measures .61" at the muzzle. A plastic 20 ga Fiocchi shell fits and I'll reload them with BP if I have to. The Magtech 20 ga brass shell is just a little too wide. I was reading that this Maynard barrel is between 20 ga and 16 ga.

[skeettx]

I take a MEC 20 gauge sizing ring and support tube and use my vice and
Imperial Sizing wax to size them

Then I use a tube with room for the primer cup to drive them out of the ring

https://www.mecoutdoors.com/600-jr-mark-5-parts

Numbers 20C and 47

Mike

p.s. If that is not enough, get the 28 gauge ring and lathe it out to what you need.

[cwtebay]

It's a Maynard smoothbore barrel that measures .61" at the muzzle. A plastic 20 ga Fiocchi shell fits and I'll reload them with BP if I have to. The Magtech 20 ga brass shell is just a little too wide. I was reading that this Maynard barrel is between 20 ga and 16 ga.Interesting! Thank you for letting me know.

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[Battis]

The 1873 Maynards had a large section of cartridge/shell sticking out of the breech. The 1882 models closed that gap.
So, in this pic, there's a Fiocchi 20 ga shell that fits, but the exposed base of the shell is unsupported, and as was pointed out to me, it might rupture. Any ideas on how to support that base? A ring of some sort, maybe washers. There's a few companies that might make the brass, but they're charging around $10 each. I don't need many so that might be the best option.
I also have a sleeve that fits a 20 ga breech and allows .410 shells to be fired. It's a little too wide to fit this chamber but I'm going to file it in a drill press.

[salpal48]

I know CH4D lists a 50 Maynard in there catalog. A size die is not overly expensive . you may want to give them a Call. they may have other

[Battis]

I'll check it out. Maynard made two smoothbore barrels - a 55 and a 64. I'm not sure what mine is.
I'm wondering if I used Magtech brass, and was able to size it down, would that exposed section of the brass also have to be supported?

[AZ Pete]

If just the base of the shell needs sizing, you might try the MEC Supersizerhttps://uploads.tapatalk-cdn.com/20200920/37d80d14be3cfbea8ef7999f80b9481e.jpg

[salpal48]

As you stated , You will need a support for the exposed case head. You can used a Bronze Bushing to act as a support. Either flanged or Non flanged. I do not know what the head size is but the theory will work. if you go to asbbearing.com, they sell flanged bronze bushing In many , may sizes . that can be cut or ground. I have used them for other application Bushing an be purchased by the piece

[Battis]

I'll check out the bushings. I'm trying to find someone around here with a MEC Super sizer.
Will the Magtech brass also have to be supported?
I'm also filing down the .410 sleeve - what the heck, I'll shoot .410.

[gpidaho]

Lyman used to make tap in sizers that worked like the Lee Loaders. I have one in 12ga. and another in 28ga. I have no idea if one would size the brass the amount you need but they can be found on Ebay at times for very little cash. Might be worth a try. Gp

[elk hunter]

I'll check it out. Maynard made two smoothbore barrels - a 55 and a 64. I'm not sure what mine is.
I'm wondering if I used Magtech brass, and was able to size it down, would that exposed section of the brass also have to be supported?

The 64 Maynard is closest to 20 gauge. I measured the 64 Maynard case I have and the solid head portion is .218 deep including the rim. I measured a Magtech 24 gauge case and the solid portion of the head measured .105 deep including the rim. I would be hesitant to use any of the Magtech brass for the Maynard since the rear of the case is unsupported. I don't think you could reinforce the outside of the Magtech case and be able to easily size it down to fit the Maynard chamber. Some early paper shotshells had a short inside metal reinforcement to support the rear of the case but I'm sure they were a press in fit to make a good seal between the paper and the reinforcement piece. If it were me I make my own cases from brass rod but not everyone has the tools and the skill to do that. Do keep us posted on your progress.

[Battis]

So, this is what I did.
I had a 20ga to .410 adaptor sleeve that almost fit in the breech. With a file and drill press, I trimmed it down to fit, leaving enough of the base sticking out of the breech to take up the headspace. I test fired a dummy .410 shell and the primer popped. I load my own .410s, so I could even use black powder.
The adaptor will push out if I ever get 20 ga shells.

[skeettx]

Great report
Well done
Mike

[Battis]

Getting the spent shells out will be a chore. Those adapter sleeves are meant to come out after each shot - they even include a little rod to knock out the empty. I'm thinking that I could cut slots on either side of the adapter and use something to pluck the empty out.
So, the bore was made to handle 20 ga black powder. I could load BP .410 shells, but I'm also thinking that with the adapter, the barrel should be able to use modern .410 shells. Any ideas on the comparison between 20 ga BP and smokeless .410?

You'd think that with all the time and thought I put into this gun, I'd be shooting it every day. Probably not...

[salpal48]

there is a person On the ASSRA form That makes and sell maynard Headspace Rings for maynard cartridge. He usually has a post in the WTS thread if interested

[Battis]

He stopped making and selling them.

[toot]

what & where is the ASSRA site? thanks'.

[Battis]

http://www.assra.com/

[Battis]

I took the Maynard to the range, set up single clay birds hanging on a string and fired away with the .410 shells (reloads and some factory loads). From 25 yds, the clay birds disappeared under the withering .410 blasts. 21 shots, no misfires. The barrel and the sleeve adaptor never even got warm. I'll try with a bird thrower next week.
The sleeve adapter cost me about $20 a few years ago. It took some time fitting it with a file and drill press, but it works. 410s can be fun.

[salpal48]

Looks like another project well done