I need a guru who knows how to fireform wildcat cases. I have a barreled action Iver Johnson M1 Carbine that has been factory chambered to accept a .30 Carbine case necked down to accept a .257 bullet. I did a chamber casting and took a dozen different measurements from that. It is a .30 Carbine case and it has a bore diameter of .257. I have an RCBS forming die set for the .22 Spitfire that will give me an almost perfectly formed case according to the measurements. I have an old magazine article explaining step by step on how to start with a 10% case volume powder charge with tissue paper wadding to hold the powder, cornmeal filler and hard grease as a case plug. I started with 1.8 Gr of 2400 and worked my way to 4 Gr but can see no appreciable difference between the forming die and the chamber measurements after firing. Thought I had better ask someone for advice before I do something dumb. The bolt will close on both the formed only case as well as the fired case. If I add one thickness of sticky file label it will still close. Two thicknesses and the bolt will NOT close. I think I have too much headspace but am not sure what I should do next.

If anyone is willing to spend some time talking me thru how to do this I would appreciate it very much. E-mail me at: dandjent@infi.net

Why not just buy a real Carbine? Cause I have a closet full of them now but not one in .25 caliber. One of only several hundred made but there is no ammo available. So! The voices in my head tell me I have to make some. Thanks to anyone willing to help.

My suggestion is to form the case with your .22 Spitfire die, then expand the neck with a .257 expander ball. Load a modest midrange load behind a bullet that is seated long enough to engage the lands and thus hold the case firmly against the bolt face. Upon firing, you should have a case which is perfectly headspaced to your chamber (and a case from which a set of custom dies can be made).

Good luck! Sounds like an interesting little gun.

I concur with Stonecreek, and will add that fireforming a gas-operated semi-auto probably works differently than in a single-shot or bolt-action.

Sometimes having something different isn't quite so charming.

Can you tell us what the cartridge designation is (stamped on the barrel, probably)?

George

Just guessing I would say that 2400 is WAY TOO SLOW for fire forming the case. This looks to be a good candidate to anneal the case neck, form (22 spitfire is doing a bunch more case working than usual, but will work) in your die, load with a fairly fast pistol powder, fill with cream of wheat (it is a little denser and "seems to work better").
point up in the air and downwind and pull the trigger.
Appropriate powder charge is best determined by trial and error!

LouisB
Just an opinion with a few suppositions thrown in to make it interesting!

Landtrain, It sounds like you are there!
Since I'm not familiar with the 22 Spitfire, I can't say for sure, but your fireforming technique sounds like mine with one exception...I form .35 Whelan from .30-06, and expand the neck up and neck down to .35 to form a small shoulder that will fit my chamber with a slight pressure on the bolt. I would think that you could start with .30 carbine brass and neck down to .25 cal and form the shoulder that will just fit your chamber and blow it out from there....just be sure that your bolt is in battery!
I envy you your collection...I loaded for and shot a friends carbine in the mid 60's, and loved it...would like to have one of my own!
To your problem, apparently you don't have a problem, the .22 spitfire must be extremely close to your chamber, so that you can't see any difference in the fireformed cases. In fact, I seem to remember from somewhere, that the .30 carbine was rebarreled and chambered to this cartridge. But, if you show me a 70 year old whose memory is as good as it ever was, I'll show you a 70 year old whose memory never was worth a damn!
Regards, Curley
PSyour e-mail doesn't work

[ 08-15-2002, 05:12: Message edited by: curley ]

I'll buy what Stone is suggesting, with a couple of questions. 1. I've always heard and have always FOLLOWED the practice of fire forming cases with a full or regular charge. NOT a reduced load. The whole exercise of "fire forming" is to exert some PRESSURE on that case to form it. Reducing the load to something wimpy defeats the whole exercise IMHO. 2. It makes me nervous to seat the bullet up into the lands. This can crank chamber pressure up real fast and often in somewhat unpredictable ways.

Those are my feeble thoughts for what they are worth.

To all who responded. Thanks. I'll try some more this week end. I questioned the reduced loads but the writer sounded like he had more experience than I did. One down, 7 to go. Thanks again.

Landtrain,

You didn't answer my question; what is the cartridge designation stamped on the barrel?

George

Landtrain, do you already have a set of dies for this round? If you have (or can get) a full-length die, I would GRADUALLY size a case until the bolt will just close on the case. Then, size all your brass to the same dimension, load them with a full-charge, and shoot. These cases are now "fire-formed", BUT, since you are starting with a .30 cal neck and reducing it to hold .257" bullets, you can TOTALLY ELIMINATE any excessive headspace with nothing more than your full-lenth sizing die by merely adjusting the die for a "crush-fit". This is easier to do with a bolt-action, but can be done with a semi-auto also.

GeorgeS. There is no markings on the barrel. It has been my experience that neither Universal nor Iver Johnson marked the caliber designation on their barrels and only cryptically on the receivers. Since the barrel was mostly covered up with stock, they just didn't put it on. I have a Tucker .22 Spitfire and it is not marked. You bought the gun and ammo for it based on the owners manual. That would have made it a lot easier though.