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Plastic hull resizing ??

2K views 7 replies 5 participants last post by  LEMEC 
#1 ·
Got me an old Acme 200 loader, big solid old beast; all metal (don't care for plastic) has tools for 12 and 16. Loaded many different hulls from gun club with no prob. in 12, I resize, but I think it only resizes metal head. Ran into something with the 16 I never encountered before. (16 is Win. M12 1939 vintage) Got a bunch of S&W 16 once fired hulls, nice cond. loaded'em up and they are terrible hard to chamber. If fired, they eject but to get one out without firing a dowel must be put down bbl. and round tapped out while pulling pump. (yeah, I know; not a great idea). I think the plastic is actually expanded, I never heard of that; is there a tool to resize the plastic hull? I read thru some items on 'search' and I think I'm right about plastic expansion, but saw no mention of a tool I could use for this. I'd really hate to have to tear down nearly a box of reloads. Anything I can do to salvage this? I've been reloading lightly since the 80's and never encountered this problem.
 
#3 ·
I had exactly the same problem with a Winchester M12 16 gauge of 1930s vintage.

I had a whole load of 16 ga cases fired in either my own 16ga SXS or other people's guns. I resized them, but they were very hard to chamber, or remove unfired. The M12 had no trouble chambering factory ammo, or reloaded ammo using cases originally fired in the M12.

I took a Vernier caliper and measured the cases I'd fired in my old Belgian 16 ga SXS. The heads had been resized and were the proper size. The plastic was several thousandths of an inch wider than the plastic on unfired factory shells.

My conclusion was that;

(1) The plastic tubes of shotshells expand on firing. Which is surely inevitable; at the moment of firing, there's one heck of a bonfire going on inside that plastic tube. Apply a match or a lighter to a plastic shotshell case; doesn't take much to soften the plastic. Now, if the gun's chamber is new and unworn, the plastic tube can't expand very much, because it's got nowhere to go. But if the chamber is a bit oversize, through wear and age (my 16ga SXS is no spring chicken), chances are the plastic tube will swell when softened by heat and take on the dimensions of said chamber.

(Once you've fired the case in your M12 chamber, of course, it'll have melted-and-reformed to fit that chamber, so it'll extract no problem. I found this with mine.)

(2) Resizing the head doesn't resize the plastic; logically enough, because the sizing ring is cut to the dimensions of the case head.

(3) My guess is that M12s of that era either had slightly smaller-than-average chambers, or else the steel used is so good it hasn't worn significantly over the last 80-odd years.

Practical answer; only use cases originally fired in that gun. This has worked fine for me. I bought 500 rounds of factory ammo and kept the empties separate from those fired in the SXS.

It may be possible to resize the plastic by, for example, turning up a full-length resizing die on a lathe, heating the cases gently in an oven to soften them up just a bit, and resizing. Haven't tried it; can't be bothered.
 
#4 ·
gg -

Lemmings post makes sense to me. My M12 is a 1926 model with 2 9/16" chamber. I've not experienced the problem that you and lemming describe, but then I don't shoot much ammo that has been first fired in other guns. I did get about 350 once fired Fed/Estate hulls that had be fired in another gun, but have had no difficulty in resizing and firing them.

Good luck with the problem. I love shooting my M12 16 ga. It may be the sweetest, most naturally pointing shotgun I've ever fired.
 
#5 ·
bprater said:
gg -

I love shooting my M12 16 ga. It may be the sweetest, most naturally pointing shotgun I've ever fired.
Agreed. It took me 20 years to find one here in the UK, but it was worth the wait. Mine came fitted with an early model Polychoke, which throws extremely good, even patterns; 21 grains Unique under a BP Trap Commander wad.
 
#6 ·
Ya know, outta sheer frustration I tried something. Measured girth of new shell, functional reloaded shell and some of these uncooperative S&Ws. New shell roughly .710+, functional reloaded shell appx. low .720s, The S&Ws needless to say were considerably over that. I found an old adjustable wrench I've had 'forever' and it has a large ('hanging?) hole in the handle that meas. .715! Using hand pressure only, no hammers or such on loaded ammo; I pushed the plastic hulls thru said hole and sure'nuf you could see the reduction in OD. They will now function in my M12 when pumped normally, delibert slowness will show some resistance, but you gotta' "ask" for it. This is exactly why I asked if there were some sort of tool available for such plastic resizing, seems there should be; it's certainly do-able if I can succeed with a darn monkey wrench!
 
#7 ·
So we're talking about a full-length sizing die here, right? I've mulled that over at times with my MEC Sizemaster after getting some hulls that bulged a tad after crimping. If one were to fabricate a die for use in the final crimp station that would swage (squeeze) the hull body down to factory diameter, would this be viable?
 
#8 ·
grayingghost said:
Ya know, outta sheer frustration I tried something. Measured girth of new shell, functional reloaded shell and some of these uncooperative S&Ws. New shell roughly .710+, functional reloaded shell appx. low .720s, The S&Ws needless to say were considerably over that. I found an old adjustable wrench I've had 'forever' and it has a large ('hanging?) hole in the handle that meas. .715! Using hand pressure only, no hammers or such on loaded ammo; I pushed the plastic hulls thru said hole and sure'nuf you could see the reduction in OD. They will now function in my M12 when pumped normally, delibert slowness will show some resistance, but you gotta' "ask" for it. This is exactly why I asked if there were some sort of tool available for such plastic resizing, seems there should be; it's certainly do-able if I can succeed with a darn monkey wrench!
I did some similar tests some time ago and i found that after sizing the plastic the hulls would indeed show a reduction in diameter, but after hours of storage they would expand back to the enlarged diameter. Heat such as burning gunpowder actually shrinks the plastic as that is what happens to plastic when it comes into contact with high heat, but when pressure is added to the mix the plastic will hold to chamber dimension and take a set although it will shrink back some. You might find that your hulls don't expand in storage, but if they do you might need some type of low heat device to help them keep their shape. I used to have an old electric shell former/redristibutor made by mec, but it was designed for paper shells.
 
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