Roll Crimp 12G Hull Length

[bosco555]

Hi all,

I'm new at roll crimping and have some 2.3/4" once fired hulls that I'd like to use. Measuring the fired shells, they are indeed 2.7" something...

To roll crimp I'd have to trim the "star/fold" crimp at its base. Would the resulting shell be too short, or OK?

thanks in advance
GB

[GhostHawk]

The easy answer to that is to load that shell.

Chances are a load designed for a roll crimp is going to be a fair bit shorter than one designed to be crimped.

I do roll crimp some loads but I am cheating and using new primed hulls. That fold crimp is about perfect to roll over.

Are you SURE you have to cut it off?

I suspect that if you do you are going to be short.

[rancher1913]

have you seen the shorty's that are available commercially. I have been doing just what you describe, started out using in a single shot and then tried them in a pump, they cycle and fire just fine.

ttps://www.cheaperthandirt.com/category/ammunition/shotgun/12-gauge/mini-and-short-shells.do

[bikerbeans]

Some fold crimped fired hulls roll crimp fine without being trimmed and some will not. Published load data isn't going to work if you trim the hull.

BB

[too many things]

ALL depends on what you want to load. you can roll anything that will suit your load.
remember that a shotcup type will be problem if you don't cut the top off.

[bosco555]

Hi all and thanks for the replies...

So I shouldn't roll crimp say a shell with a lee 1oz key slug in a 1oz shotcup wad? I will be roll crimping mostly .690" Lee RB. Got some equipment from Ballistic Products, roll crimper, hull vise and the trim doctor..What I gathering here is that I should play with the wad/filler wads until I get the desired height?
thanks
gb

[Moonie]

I roll crimp 1oz Lee slugs in 1oz wads just fine.

[bosco555]

I roll crimp 1oz Lee slugs in 1oz wads just fine.

Do you guys leave the wad petals as they are or trim them off? Sorry...just trying to learn..

thanks

[Cap'n Morgan]

You don't have to to trim to the base of the star crimp. If you just remove the skived part (about 1/8") you'll have no problems.

[GhostHawk]

I have both star crimped and roll crimped shells with slug loads. All comes down to wad choices and how tall your total load is.

Powder choice and charge can also effect this.

I have been having good luck doing both. I mostly use the Pt 12 05 and Pt 12 15 wads from Ballistics products. 6$ for 250 wads makes them pretty economical to use. The 1215 is a 1 or 1 1/8th oz wad. The 1205 is a 7/8ths oz wad and the shot cup is significantly shorter. I have been putting half of a 20 ga nitro card under the slug in most of mine. This lifts the slug just enough so that I don't have to worry about trimming petals.

With shotgun the devil is in the details. Find a recipe that uses components you have and then test, adjust, retest.

[bosco555]

Thanks all...Unfortunately here where I live in Aus we don't have access to a lot of powders..we usually use ADI AP70 (Universal/Unique equiv) and ADI AS50N (International/Greendot equiv). For wads I have bought claybusters CB1118-12 for the Lee slugs and CB1114-12 for 00 9-ball buckshot (from BPI)

Will give it a try and if no good I'll get some 7/8th oz as ghost says...It does make sense instead of buggering around with inserts and filler wads..
Thanks again guys...really appreciated

[bosco555]

The one on the left was trimmed by 1/8" or 3mm...Maybe first attempt, but it looks like the dog has had a go at it...the blue one was deprived of the entire fold crimp and although is 2.2" long it looks OK..

[OnHoPr]

They make a cone shaped tool called the Spin Doctor. It goes in the drill press and you can smooth out the fold memory of the crimp. You could probably take a 3/4" hardwood dowel and do the same thing. Get a piece of dowel, find center, drill a hole to accept a 5/16 long lag bolt or eye screw, insert bolt or screw, cut off head or eye, chuck in drill press, sand to coned smoothness to appropriate size to iron out crimp memory. It will take a little getting use to the crimping process.

[trapper9260]

I had made up my own 2" shells and I made some roll and fold and I did not change the data .Just how long I have them for fold and roll.They shot fine for me.i also done some the is about 1 3/4" too and no problems But those if you use a pump you will have to have it not a bottom feed and discharge. but the 2" will cycle fine in the pump.

[NoAngel]

You need a 1/4" to roll crimp.
If you have a 2 3/4 shell, load it appropriately and lay your over shot card on top. Measure. Anything more than about a quarter inch is not needed and can be trimmed.

[NoAngel]

Published load data isn't going to work if you trim the hull.

BB

That's not entirely true. Following the load recipe and trimming off what is not needed for a good roll crimp changes nothing.

[rancher1913]

some recipes call for a roll crimp and some call for a fold crimp only---so watch that and don't get them mixed up.

[Moonie]

I do not trim my wads.

[Reverend Al]

Just playing the "devil's advocate" here, but if you need / want some "clean mouthed" hulls without a previous crimp memory for roll crimping at 2 3/4" fired length for slug use why not just shorten some 3" fired hulls down to the required 2 3/4" length? For slug use I wouldn't think you'd need to do all that many of them? Just a thought ...

In my case I've usually shortened fired 2 3/4" crimped hulls to about 2 1/2" length (trimmed to just below the old folded crimp mouth), loaded them with an appropriate length of wad column and roll crimped them. I also have the advantage of owning several of the old style electric case mouth heaters for "freshening up" old paper shells and have had very good success "ironing" out the case mouths of shortened plastic hulls too. The heat seems to help stiffen up / harden the mouths of the plastic cases and then you get a good, solid roll crimp that seems to hold indefinitely.

Just my 2 cents worth ...

[NoAngel]

Reverend Al is exactly right SO LONG as the 3" hull has the same base wad as the 2 3/4 recipe you are using. It works and I do it regularly. I find a good number of 3" Rio hulls at my range and trim them down.

It has been my finding though, MOST 2-3/4 loads have plenty of length to them to cut off the fold crimp and leave yourself the needed 1/4" to make a good roll.
In the last few years I have abandoned fold crimps altogether and use a clear overshot disk from BPI. You can SEE what is inside the shell and that's great for me.


This is a 16g [sadly, they don't make clear over shot disks for 16g] It's a 2-3/4 shell but measures closer to 2.5 inches [uncrimped] I took a 2 3/4 hull, loaded it with the appropriate recipe from my book, dropped a over shot card and measured from the top of the card to the hull mouth. Subtract .250 and that's how much you remove. Load normally skipping the fold crimp and going straight to the drill press with a roll crimper. Easy. Slower but I enjoy the process and there's no denying, a clean roll crimp just looks NICE.

What lead me to roll crimps was the frustration of finding the right wad, hull combo to carry the payload I want to shoot and end up with the perfect shot column to get a good quality crimp. With a fold crimp, there's no wiggle room compared to a roll crimp.


You don't want TOO much pressure inside the case but if you look closely at the over shot disk, this round ball load leaves a slight dimple on the thin card. I KNOW the components are all snug inside.