How short can you trim a shell roll crimping

[Keith]

With roll crimping from a new shell, how many crimps before cutting and how short can one cut?
When it gets too short for a cushon wad can shorter stacks of card wads do the trick with the same powder charge?
Saw this photo. Looks pretty short.
Sorry photo would not copy. Ebay link might.
https://www.ebay.com.au/itm/12-or-20-Gauge-Shotgun-Roll-Crimping-Tool/162527361340?ssPageName=STRK%3AMEBIDX%3AIT&var=461531619880&_trksid=p2057872.m2749.l2649

I am talking round ball loads here. My C-More has a 3 inch chamber anyway

[NyFirefighter357]

They sell Mini & short rounds The shortest being 1.75"

https://youtu.be/s80swBxJ_Es

https://www.thetruthaboutguns.com/shotgun-mini-shells-a-shotgunner-on-their-advantages-disadvantages-and-best-uses/

[megasupermagnum]

With roll crimping from a new shell, how many crimps before cutting and how short can one cut?
When it gets too short for a cushon wad can shorter stacks of card wads do the trick with the same powder charge?
Saw this photo. Looks pretty short.
Sorry photo would not copy. Ebay link might.
https://www.ebay.com.au/itm/12-or-20-Gauge-Shotgun-Roll-Crimping-Tool/162527361340?ssPageName=STRK%3AMEBIDX%3AIT&var=461531619880&_trksid=p2057872.m2749.l2649

I am talking round ball loads here. My C-More has a 3 inch chamber anyway

How many loadings you can get will depend on the load, and what shell it is. I would say 5 loadings would be reasonable, but 10 or 15 is not out of the question. Light target level loads, you may get closer to that 15 mark. You can use card wads, but the powder charge will have to change. It is not impossible to find old style load data for 2 1/2" hulls. You could then cut them down and use less wadding. Depending on how deep you are crimping, you might be able to get away with trimming 1/8" at a time. At some point you can compromise reliability with a short hull in a repeater like a pump or semi auto, but they should all function great on 2 1/2". It isn't until you get into the special 1 3/4" shells that reliability becomes an issue.

[swamp]

With my roll crimping tool the shortest I can cut is 2 1/8. The ram the roll crimper is on will not give a decent crimp shorter than that. Mounted in a drill press is different.
swamp

[toallmy]

I can't really say how many times you can reuse the hull , because a lot happens in a hull every time you shoot it . I generally toss hulls after 5-6 uses with light loads , and a couple heavy loads but that's with standard fold crimps .
My role crimp shells are made out of the previously fired hulls that I don't plan on reusing . I pick a stack of the components I want to load and then cut the hull to the height to fit the components and do a good role crimp . I don't keep cutting the hulls shorter and shorter . For fun back yard shooting I will reuse a previously roll crimp hull a couple times , then dispose of it . Keep in mind I keep a trash can full of cheap Winchester & federal hulls in the basement just for disposable hulls . I keep my good hulls stored separately .
In theory you could shoot a hull until the crimp burned up then start cutting it down until the primers need reconditioning , but the hull would probably get burnt and crack before reaching that point .
I just measured one of my cut off roll crimped Minnie slug hulls loaded length is 1.725 . That held my powder charge + a wad with the crush section cut out , with my slug sitting in the shot cup on top of the wad base as a gas seal with a good role crimp . This shell is used for back yard blasting not home defence , or hunting because of possible failure to feed issues .
Be safe

[Cap'n Morgan]

Just a quick warning that can't be repeated too often: Unless you have the correct loading data for a given shell length, you must be careful when shortening the shells. Fast burning powders are very sensitive with regard to the free volume/space under the payload. The cushion part of a plastic wad is mostly "free space" and collapse easily. If replaced with with a felt wad of the same length, pressure will rise, and even more so if replaced with hard cards. Think of it as a change of seating depth in a straight case handgun load.

As an example let's take a 45 LC loaded with 7.5 grains Unique behind a 255 grains bullet seated .40" deep. It will take up 50% of the case volume and create a pressure of about 12400 psi.

Seating the bullet to a depth of .61" will reduce the free space between powder and bullet from 50% to 25%. This will raise the pressure to 21800 psi, way above the SAAMI max of 1400 psi.

Of course this is not a shotshell, but the principle is the same (fast powder in a straight case) and the jump would be even higher with Red- or Green Dot.

[W.R.Buchanan]

Good point and let me add this. Shotshell hulls vary greatly in composition. Some hulls can be reloaded many times others maybe once or twice.

I have old style Win AA's that have been reloaded 8 times so far and only get tossed when they split at the crimp. I paid 4 cents each for them! I could toss the whole lot and not suffer financial ruin!

I have a bucket with 2500 O/F new style AA's I bought for $100,,, once again 4 cents each. They will keep me in shotgun shells for the rest of my life. I'll probably never use them up as Walmart sells shotshells for $21.74/100 or <.22 each, and it is hard to reload for less than that nowadays.

Those AA hulls don't roll crimp all that well so I don't use them for my Slug Loads. They are for Trap and Skeet Shooting.

Hulls that do crimp well usually have been roll crimped from the factory. I really like the Blue Federal Low Recoil Slug Hulls. I can get about 2-3 reloads from them with my hull mouth reconditioning process. (Rotating Mandrel with Heat Gun) which brings them back nicely. I pick them up off the ground when I goto a class so they are free, but I did buy a Harbor Freight Grabber($10) so I don't have to bend over to pick them up now.

New Rio Hulls from BPI are 11-13 cents each so 100 of those will cost you $11-13? 2-3 reloads with them. I toss them because they look bad not because they are worn out.

Next point is,,, how many slugs or balls are you going to shoot? Even if you are plinking with them? I have shot about 100 slugs in the last year in Classes, in 3 gun shoots, and at the Range. I don't get to hunt much any more, but even if I did I'd be looking at maybe 5-10 more in a year. Some guys are doing alot of testing so they probably shoot alot more, but those guys also will toss hulls that have been reloaded a few times simply because the cost of those hulls is built into their hobby money, and they want to only load High Quality Ammo.

Then we could get back to Caps point about pressure issues due to varying wad pressures, which would be a result of not having any valid load data to use directly or even interpolate from for shorter shells of unknown length. This could be the biggest reason not to push this any further.

The Risks far outweigh the Rewards! Are you willing to risk a catastrophic failure or blow up a gun, or yourself to save a few cents?

My Philosophy on reloading anything is this,,, If you are going to stray from established and tested load data, the only direction to go is down. Anything that could increase pressure must be considered very carefully and if you aren't 100% sure what you are doing is not going exceed Limits for whatever cartridge you are loading,,, then you probably shouldn't do it.

Your safety is up to YOU!

My .02

Randy

[gpidaho]

Keith: You can get short shell reloading data in a small loading manual from BPI. It is somewhat of a catalog of BPI products but good information none the less. Gp

[Keith]

Thanks, lots of good info there. I bought BPI,s slug reloading book from the local agent but its sold out. They have more stuff coming soon. I was getting some wads and all too.
I dont have any range pick ups here so I am buying new no name hulls from my LGS They are white just with 12 gauge on the headstamp. They are not particularly robust. Just working out how many times i can get a roll crimp from new then cut that off 1/4 inch, do some more then cut another 1/4 inch and so on.
With 20 grains Unique and a 12S0 wad I put 4 cards under the ball and trim the petals. As I go shorter I can remove the cards and trim the petals more but only to a point I guess. I still have not got my load sorted yet. Hoping I wont run out of hulls before I do.

[hollywood63]

[QUOTE=Cap'n Morgan;4884299]Just a quick warning that can't be repeated too often: Unless you have the correct loading data for a given shell length, you must be careful when shortening the shells. Fast burning powders are very sensitive with regard to the free volume/space under the payload. The cushion part of a plastic wad is mostly "free space" and collapse easily. If replaced with with a felt wad of the same length, pressure will rise, and even more so if replaced with hard cards. Think of it as a change of seating depth in a straight case handgun load.

Cap'n if you were to replace felt wads with a plastic wad with a cushion would it be a safe comment that the pressure could/would go down? As long as the load column was the same of course.

[Cap'n Morgan]

Cap'n if you were to replace felt wads with a plastic wad with a cushion would it be a safe comment that the pressure could/would go down? As long as the load column was the same of course.

Normally I would say yes, but I have found that adding a plastic seal between powder and the felt wad will increase velocity slightly (= more pressure) even when reducing the the height of the wad to compensate for the height. Plastic wads are designed with the seal as a part of the wad so swapping felt wads for a plastic wad could actually raise pressure, but only an actually test using a pressure tester (or a chronograph) can tell.

[bikerbeans]

FWIW, I have used a bpi 12ga roll crimper on a drill press to load mini shells for 3-gun shoots. The finished length was just shy of 1.5". Load contained powder, 1/8" fiber wad, #6 shot and an OSC. Good enough for 15 yard shots but a pretty pathetic load. Also took a lot of practice to cycle correctly in a keltec double mag tube scattergun.

BB