Rimfire Wildcatting

[Zorro]

Looking for information about Wildcatting Rimfires.

Specifically I want a FMJ or solid copper bullet option for the .17 Winchester Super Magnum Rimfire.

[bacardisteve]

I know there are kits out to reload 22lr but from what i understand they are a real pain to use. Dont believe anyone makes a kit for reloading any other rimfire and im sure most bullets available to reloaders in .17 are designed for centerfire. As far as wildcatting something based on winchesters new rimfire case I think that would be a very tall order and crazy expensive.

[griz]

I believe that many years ago some silhouette shooters had a big run of primed, empty 22 mag cases made in order to load them with more knockdown power. I don't know if there are any still to be had, but that is the only place to start that I can imagine. And then you have to worry about dies and finding a FMJ bullet that small. If it would match your intentions one option would be to pull a bullet from a regular round and load it backwards.

[Unclenick]

CAUTION: The following post includes loading data beyond or not covered by currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assume any liability for any damage or injury resulting from use of this information.


Zorro,

Nosler, Hornady, Berger and Remington make 17 caliber bullets. I don't spot any FMJ's or solids among them, so what follows remains fantasy football at the moment.

Should the bullets become available, read this article on the differences modern bullet types make to pressure.

This is a 33,000 psi MAP cartridge and the polymer tip bullets in them now are jacketed, and groove and bore diameters match those of current centerfire 17's. Thus, substituting equal weight, equal length or shorter jacketed cup and core bullets, like an FMJ, might be made to work. Solid copper would cause problems (see last paragraph).

You would get the primed and sized case and appropriate powder by pulling bullets from live commercial ammunition, which is expensive and wastes their bullets. Even though a nail gun blank is the parent case, it would be dangerous to attempt to unload those, as blanks typically use a faster and more violently explosive powder than bullet propellants are. You would have to find an appropriate powder to propel the bullets. That discovery process has a lot of potential to pop rims and damage your gun by gas cutting as you try to find one suitable for the large expansion ratio gun.

Even if you got the necessary forming dies made and unloaded the blanks successfully, unlike centerfire Boxer primers, which have a paper or foil cover over the priming mix and often also have sealing lacquer over that, the rimfire priming mix is usually exposed inside the case and would be more vulnerable to case sizing lube contamination. Also unlike priming mix in boxer primers, which is designed to flex enough to have the anvil compress it slightly when the primer is seated, rimfire priming mix can be brittle and vulnerable to mechanical damage. As a result, handling in presses and specially made shell holders may cause the mix to break and fall out of the rim, producing duds. Rimfire priming mixes are meant to be added after the case is formed.

If you ever find an appropriate FMJ the same weight as is in a commercial cartridge, I would reduce the powder charge you find inside a pulled cartridge by 10% to start. This is in case the new bullet is tougher to engrave. You would then work up in 2% steps if that fired OK (reduce 8%, then 6%, then 4%, then 2%, then full load), watching for signs that the rim looked any harder flattened or more expanded or more sharply marked by the firing pin or other bolt face features. You would go back down to the previous step and declare it to be your maximum load if any of those signs appeared.

Solid copper bullets will increase your pressure. Even if they weren't harder to push into the rifling, for a given weight, since copper is less dense than lead, it will take up more space in the case, thereby raising pressure. You may find you have to reduce the powder charge so much to avoid getting pressure signs that your muzzle velocity is no longer acceptable. A solid copper bullet's greater length for the same weight may not be properly stabilized by your rifling twist rate, especially with lower muzzle velocity. If I were to try such a thing, my first load would be with 16% less powder than is found in a commercial round for the same bullet weight, and I would work up from there in 2% steps as described above, but over that wider range.

[Jim Watson]

Unk covers it pretty well.
All I can add is that I have read detailed accounts of BPCR loading .22 LR and there is not much off-the-shelf equipment involved in handloading rimfires. There is a lot of adaptation, improvisation, and fabrication required.

[Zorro]

All things I had not considered.

Specifically I would like to use the round on coyotes.

That small bullet is hitting 3000 FPS and I want something that is designed to penetrate deep for the caliber.

I'm not convinced it won't blow up if it hits a shoulder or go deep enough on a quartering away shot on something coyote sized.

Maybe someone will make a round for it with a guaranteed 12 inch deep penetration.

[griz]

I wondered what the goal was. I don't have any experience with coyotes at all, but I would be concerned that a hole that small, even through and through, wouldn't be enough damage to stop it. Again, no experience.

[Mobuck]

jousting with windmills

[jmorris]

Not sure if changing a bullet counts as "wildcatting", is that all you want to do is pull a bullet and install another in its place?

[Zorro]

Well minimal Wildcatting at least. I did not know it was possible until recently.

[shootbrownelk]

Just buy a .17 caliber centerfire and end all the hassle. It ain't worth it.