223 wildcat

[ckrockets]

I was thinking about developing this 223 wildcat round.

Its main purpose would be a for cheap practice round using plated 30 carbine bullets pushing them around 1800 fps.

A load for jacked bullets could be developed which could be 2500 fps + I imagine.

Possible names: 300X45, 30 Super Carbine

For heavier bullets you could use projectiles developed for the 30-30.

Comments?

[Doc Highwall]

I think it is to close to the 300 Black Out.

[ckrockets]

ummm...

300blackout = 7.62X35 (using 5.56 donor case)

what i'm proposing = 7.62X45 (using 5.56 donor case)

more case capacity means less pressure for the same load so one can up the powder charge increasing velocity

[JIMinPHX]

I think that this has been done in 7mm, 7.62 & even 8mm. I don't believe that it ever really caught on, but I can't understand why. I think that this conversion makes a lot of sense.

Personally, I'd like to do the same thing in 6.5mm with a 130-gr boolit. I think that it would make for a nice little low-recoil round for game up to small deer & be very powder efficient to boot.

If .30 cal trips your trigger, then stick with .30. It should be a fun little play toy.

[DeanWinchester]

Sticking to the "nothing new under the sun"

7,62x40 Wilson Tactical. Wilson Combat already made the "300 BLK Long"



....also, the Czechs already made a 7,62x45 many moons ago.

[texassako]

Are you stuck on that case size? Wildcat and cheap usually do not go hand in hand. 7.62x39 has a little more capacity than what you propose and about the same ballistics. You might want to seat one of those heavier bullet to see how long it ends up being as well.

[MT Gianni]

I am not sure that it would do more than the 7mmTCU which has readily available dies and data.

[ckrockets]

the 7.62X45 czech is basically a 7.62x39 Russian case lengthened...oranges and apples

what I'm proposing is a 5.56X45 case sized up to fit 7.62 projectile with a high cannelure/ogive(such as 30 carbine and 30-30 projectiles)...so they still fit and function in 5.56 magazines...did you pay attention to the mockup pic i posted?

so my proposed 7.62X45 should out perform the 7.62X40wt...

[uscra112]

First of all it has already been done numerous times. The only successful one is the .300 Blackout. Second that case shape will always have serious headspace problems because it lacks a decent shoulder. Some have tried headspacing on the case mouth when stretching that case for large bullets, but that has its' own problems, which could be quite serious. At the very least, if you pursue it, it needs a very sharp shoulder. Look at the .35 Whelen Ackley Improved for guidance.

[EMC45]

Get a Blackout upper and ream it longer and BAM! You got what you're aiming for. (In theory)

[john hayslip]

I just loaded a few blackouts with a round nose bullet with a soft point similar to the one in the picture on the left and tried to shoot it but the bullet apparently jammed in the leade and wouldn't allow the bolt to fully close. Could hear the firing pin click but no indent on primer. Going to have to trouble shoot today - I have some pointedy 110 grain bullets and will substitute them and see if that is in truth the problem. If not I'll check the shoulder length but I'm pretty sure that's correct.

[longbow]

It has been done a long time ago.

I have an article by Roy Dunlap (IIRC) on the .30 Apache which is simply the .223 necked up to .30 cal. Also .30-223 was an early entry into metallic silhouette shooting according to Elgin gates.

So, yeah, nothing new under the sun is right. Not a bad idea though and I am a bit surprised it didn't catch on as an economical .30-30 level round using surplus brass. It should be easy to load up supersonic to decent ballistics and down to subsonic without much trouble. I have thought about it myself.

As mentioned though, nowadays there is so much 7.62 x 39 around it is easier to use that.

Longbow

[oldred]

I think the days for creating something truly new are long gone, not saying that a different wildcat can't be done but there is just so much over-lap from so many efforts both past and present it's almost impossible to create anything different enough to be worth the trouble and expense. The exception might be the "sub" calibers of 20 caliber and smaller but everything else has been done in just about every imaginable way, still doing something unique is fun even if it only closely duplicates another similar round and after all fun is what this is all about.

[357maximum]

30TCU, and 8mmTCU have been successfully used in single shots and bolt guns. Do not let that "shoulder thing" bother you. Those that can pay attention have no issue with them. Most them people that have problems with minimal shoulders..... simply have S.D.A.D.....sizing die adjustment disorder. The same souls also have issue with the 30/35Herrets, the 30/30 and the 35 remington in contenders, and the Whelen's in bolt guns......some people just cannot be made to pay attention enough to properly adjust a sizing die enough to make the brass match the steel in THEIR GUN.


Not to knock the good idea fairy but in this case I would point you to the 7TCU....much cheaper to build/buy. I run mine at 2512 fps with a 135grain cast boolit with M.O.A or less accuracy, and it sure kills deer dead.

http://castboolits.gunloads.com/show...arbine-Venison

[dk17hmr]

.......so my proposed 7.62X45 should out perform the 7.62X40wt...

It has the potential to out perform with lighter bullets but with heavier bullets I think your case capacity would be the same or close to the same. The down side there is to get your bullets to work in an AR15 (assuming that's what this is for) magazine your limited on length, in your case a heavier bullet would likely be seated deeper than the ogive though, but like you say 30 carbine bullets would be the bullet of choice anyways. I have a couple wildcats based on the 223 case and really like them, they do what I want them to and give amazing velocity for the little bit of powder you have to use.

[Reverend Al]

I remember reading that article in Gun Digest about the .30 Apache wildcat (can't remember when it was published, but it might have been in the 1970's?), which worked out very well for Silhouette Rifle with bullets as heavy as 168 grains! He built his test gun on an old 788 Remington that started life as .222 Remington. If you can find the GD article you might want to look through it for some ideas on your possible project gun?

[ckrockets]

Could you scan and post the article? Thanks.

I have an article by Roy Dunlap (IIRC) on the .30 Apache which is simply the .223 necked up to .30 cal. Also .30-223 was an early entry into metallic silhouette shooting according to Elgin gates.

[barkerwc4362]

I have an AR in 7.62x40 and a case length of about 40mm is the max for .30 if you are going to use the AR format. Magazine length cartridges with bullets longer than about 135 grs push the bullet way down in the case and put the ogive up in the neck. That reduces case capacity and cause problems with neck tension. I played around with making a slightly longer case (about 42mm) trying to get a little more performance out of the 5.56 case with 125 - 135gr bullets, but gave up. The case neck needs to be positioned at the full diameter part of the bullet to ensure good neck tension and to retain the bullet without crimping. Get an AR magazine and adjust the case length and you will see what I mean. Oh and I use AA-1680 to get max velocities at reasonable pressures.

Bill

[longbow]

Here you go

[TCLouis]

JIMinPHX

I think they refer to your wish as 6.5 TCU