.30 Luger/ 7.62 X 25 Contender barrel?

[red caddy]

I've been doing some load developement for my CZ-52 and now I want to work with a longer barrel length.(longer than a PPSH) Has anybody ever seen a 16 to 22 inch .308 bore barrel for a Contender chambered in either of these rounds?  I'll need to arrest the usual suspects I guess, (Bullberry, SSK etc.) but thought I would ask here first... Thanks, Paul.

[securitysix]

I've sort of wondered the same thing, but never really looked into it.  Military Gun Supply does sell a PPS-43 clone that comes with a 16" barrel and is semi-auto.  At $750, though, it'll cost a bit more to get than a Contender barrel.

[Czech_too]

As much as I might like to have a barrel in 7.62x25 to go along with my CZ-52, I don't think I could handle the cost.  Just with browsing, it doesn't look like anyone currently does it, so you'd be looking at the cost of the reamer along with the other costs involved.

On the plus side, at least you wouldn't have to 'try' to find your brass!

Brian

[fireball168]

I've done a couple of Savage bolt barrels in 7.62x25, still have one 17" 1/12 twist here that I experimented with.

Had PTG make a reamer with a .309" throat, as most of the surplus was .3085 or smaller.

I plan on getting a couple of Contender barrels made, at least one fast twist and one slow twist just to play with.

[Czech_too]

Please keep us apprised of the results on this.  There is some interest obviously and another Contender barrel in the collection isn't necessarily a bad thing.

Brian

[Reed1911]

Shoot me an e-mail folks if you want one, we'll get them made for you no problem at all.

[red caddy]

Alrighty then, Ron can make a barrel, any way I want it, so now i have to nail down the spec's.

My original thought was to try to improve the speed and accuracy of this great little cartridge with a longer barrel. My CZ-52 will shoot minuet of pop can @ 100 Yds. and I can reliably hit moving targets (varmint size) at that range, as can my shooting buddy, with his. This, coupled with the round's ability to breach soft body armour, from a pistol length barrel, in a compact platform, is what gives me a warm fuzzy for the baby .30.

we've come up with a very accurate H-110 load, using an 85 Gr. jacketed soft nose that clocks at 1650 FPS and is not unpleasant to shoot. I want to do some research with lighter, faster rounds. I'm going to hollow point some of the 85 Gr. to get the weight down around 70 Gr. to see if the accuracy suffers. If not, I'm going to try some 50 Gr. .224's in a sabot. (53 Gr. total)

It seems that I'm comming late to the party, as some of you guys are light years ahead of me in experimenting with this round. Hopefully, you will share your results and what uses you have found for the combination. I don't want to burn fistfulls of money trying to re invent the wheel or end up "all dressed up with no place to go...

Let the games begin... Paul

[Ken ONeill]

I have an SSK stub barrel, so obviously they can and do make them also.

[fireball168]

Shipping my reamer and gauges to MGM here in the next week or two with my next batch order.

If somebody wants one - a few $$ for reamer rental and you can order want you want direct from Shelsie.

[red caddy]

I'm thinkin' that since I want to experiment with lighter bullets, mostly, I will want a fast twist and a short throat as this will help the accuracy of the Millsurp stuff I have as well as the hotter subgun rounds that are availible.

With the small case capacity, a 22-24 inch barrel might be overkill, has anybody done the math for optimum length ? The optics I want to use pretty much negates the sight radius considerations, so I think I want to let function guide form. waddya think?

With a bullet weight of 85 Gr. and under, would a twist rate of 1 in 9" be too fast? What effect would the fast twist have on a 110 Gr. (like the Sierra 2110 spire point hollow point flat base) bullet, That's about the heaviest bullet I will ever want to use in this barrel.

 With the lighter weight bullets, this round is going to be well inferior to the 7.62 X 39 in stopping power, so, other than poppin' 'cans and punching paper, (very accurately, I hope) what are it's strong points ? (usefullness)   

OK guy's, take me to school..... Thanks, Paul.

[securitysix]

I'm thinkin' that since I want to experiment with lighter bullets, mostly, I will want a fast twist and a short throat as this will help the accuracy of the Millsurp stuff I have as well as the hotter subgun rounds that are availible.

Lighter than what?  Lighter than the milsurp stuff out there?  Faster twist is for longer bullets.  Lighter bullets are shorter, not longer.  Stick with the standard twist rate for the cartridge, and it should handle lighter bullets fine.  If you want to set up specifically for the lighter bullets, a slower twist might do, but you might sacrifice accuracy with the milsurp.

Also, I'm not sure a shorter throat is necessarily a good idea, especially if you're going to be shooting the "hotter subgun rounds" through it.  Shorter throat means shorter jump to the lands, which means pressure will rise sooner, and quite probably higher.  On an Encore frame or in a bolt-action, that's probably not going to be an issue.  On the Contender frame, I'm not sure I'd do that. 

If it were me (and it's not mostly because I can't afford to jump into a project like this right now), I'd either A) stick with the standard throat, 2) get a slightly longer throat which will probably have a negative effect on accuracy, but will reduce pressure build to some degree and allow me to use the hotter subgun ammo, or 3) get the shorter throat cut, but only shoot factory ammo (assuming the first couple of rounds of such don't show pressure signs) and handloads tailored to the barrel.

With the small case capacity, a 22-24 inch barrel might be overkill, has anybody done the math for optimum length ? The optics I want to use pretty much negates the sight radius considerations, so I think I want to let function guide form. waddya think?

I'm sure there's a formula out there to calculate optimum bore volume (length as well as diameter) for a particular powder/bullet combination, and such a formula would probably get you in the ballpark for other powders appropriate for the cartridge/bullet in question, but I surely don't know what it is.

If I were to take a guess (which I'm about to), I'd say between 16 and 18 inches would probably be pretty close to optimum, with diminishing returns beyond that up to 21 inches, and anything much more than 21 would start to show a velocity loss.  That's just a WAG, though.

[fireball168]

Here is the write up I did elsewhere from my testing with the first Savage barrel I did in 7.62x25 (it is listed in the General Classifieds right now).

17" 1/12 twist McGowen stainless, .309 throat diameter, unmodified throat length.

Since I wrote this, I've shot up to the 135g Matchking (1680 fps with the first load I tried).


I've been fascinated by this chambering for years, with the influx of the surplus ammunition - even more so.

Several months ago, I sourced a 7.62x25 reamer, tightened up some of the dimensions a bit, namely the throat, and made up a couple of barrels.

Along the way I made a chamber gauge to make it easier sneaking up on maximum OAL, and to check the various surplus for size.

I found the surplus is all over the place. Projectile diameter varies from .3055-.309, the headspace dimension has been from .020" short to .005" long.

Unfortunately, that's not the only thing that's short - so was brand new Starline brass to the tune of .015-.018" between cases(see below).

First set of dies was Lee marketed as 7.62x25, they didn't touch the shoulder, at all, on any of the cases I had on hand (Winchester, S&B & Starline). The seating die was absolutely useless, I never got a single projectile seated without crumpling up the neck.

After a bit of reading, it would seem some believe the 30 Mauser is the "same" case. I'm not completely sold on that idea as of yet.

As Redding markets a 30 Mauser die set, they were on the doorstep in short order.

The Redding dies worked like reloading dies should work...but they size the brass back to the same dimension as the Starline brass mentioned above.

Hmm.

Anyway - the inital testing and barrel break in took place with some Winchester commercial 7.62x25 loads. Nothing crazy, velocity averaged 1750 fps, 50 yard accuracy was about 1.5".

Here's what we tried today.

Reloading disclaimer - these loads were fired from a bolt action rifle, with non-standard chamber dimensions. The use in any other application is not recommended - use good sense.

Savage 10 action(crappy factory trigger that I need to replace) sitting in a BVSS stock, varmint barrel contour, Leupold 4.5-14x, Hart rest, chronograph at 6' from muzzle.

These are all fireforming loads, I didn't reload any of the previous Winchester cases - these are all using S&B once fired brass (out of handgun).

Hornady 90g XTP sized to .308" (from .309"), Lil Gun powder, .010" off the lands.

11.5g = 1940 fps 1" accuracy at 50 yards
12.0g = 1975 fps .750" accuracy at 50 yards
12.5g = 2005 fps 1.25" accuracy at 50 yards
13.0g = 2030 fps 1.5" accuracy at 50 yards
13.5g = 2060 fps 1.0" accuracy at 50 yards
14.2g = 2150 fps .625" accuracy at 50 yards (case is completely full - lightly compressed)

Sierra Varminter 110g HP, Lil Gun Powder, .010" off the lands.

12.0g = 1890 fps 1" accuracy at 50 yards
12.5g = 1940 fps .750" accuracy at 50 yards

Surplus

Marked bxn 53 1, shipped on stripper clips

Velocity = 2000 fps 2" accuracy at 50 yards

Marked 10/54

Velocity = 1890 fps 1.5" accuracy at 50 yards


Of course, recoil is non-existant, there's a little bit of torque from the rifle on the bags when firing, but it barely comes off target.

It took about 20 shots to be able to tell a temperature difference on the exterior of the barrel. The barrel life should be nearly infinite.

Pressure signs - none to be found on any of these loads.



I've got an order going in with MGM shortly - if somebody wants a barrel made, I'll ship the reamer and you can order whatever you'd like from Shelsie directly.   Send me $10 or so for the reamer rental and I'll be happy.