Luger Heavy Barrel Not Cycling
 

So, I got around to re-barelling my Luger, and ran into an issue when test firing my Fiocchi .30 Luger rounds. Hand cycling the gun works perfectly, toggle snaps down and strips, chambers and fires a round without any issue, but the gun will not extract and eject. I believe that the heavy barrel is slowing down the upper assembly, and the bullet (and remaining pressure) has left the barrel before the toggle can be opened by the coupling link. Any idea how to make the old girl cycle?

And a construction pic, just to taunt ;)

I would guess that its just too heavy for a 30 luger....

There are several guys on here that are very good at this sort of thing and will come on in a bit.

With that large long and heavy barrel you are running into the same problem with .30 Luger that a Luger carbine has..it requires a slightly stronger load to cycle. I am not one of the guy's that are very good at this sort of thing as Ed says..just a wild guess.

Caution - caution

When you step up the powder charge try to hold the unit
with both hands. The energy of the explosion goes throughout the gun and your body will be needed to help absorb some of that energy as it runs the cycle of the gun.
Jack

What about cutting a coil or two from the mainspring?

You might consider reducing the main/recoil spring weight. Wolff springs sells reduced spring weights for the P-08.

Is your extractor attempting to remove the spent brass?

You will most likely have to "play" with different approaches to get you P08 to function correctly. I would be very cautious about trying to reload the 30 Luger brass to a lot higher velocity level than factory. You well have a new strong steel barrel, but have a 90 year old frame and toggle assy.

If you are a reloader, you could produce a small number(say 10) of each powder level, increasing 0.1gr of powder for each group, watching very closely for over pressure.

When you have to manually extract the cartridge case, do you do this by hand operating the toggle train?

Do you feel any particular resistance early in manually extracting a fired case?

If so, you might have some shape or surface finish issues in the chamber.

If you adjust spring length / tension be sure to use some masking tape at the rear of the frame between the receiver ears where the rear toggle will hit the frame. If recoil resistance gets too light, you could end up peening this area.

I have a set of Wolff springs on order. I do so very hope that using the reduced power spring will fix everything, however I realize ammo may need to be changed around. I'm thinking I would start with a heavier bullet before I start increasing the charge. A heavier bullet should keep the same recoil energy needed to unlock the toggle, but should stay in the barrel longer and keep enough pressure to extract, eject and load a fresh round into the chamber. Has anyone played around with 110 gr. bullets?

Yes, currently extraction and ejection has to be done by hand. There is no noticeable resistance encountered, the pistol still extracts the case about 1/8", but doesn't have the pressure to open the toggle completely. However, receiver cycles far enough back to recock the striker, and I can "fire" the gun on the already fired case. Chamber is cut perfectly clean, and done so with a brand new reamer, so no surface finish issues there.

As to the peening issue, are you referring to the tab/protrusion at the very back of the rear toggle, which stops the upward rotation of the rear toggle, or are you talking about the surface at the back of the pocket inside the frame, just above the lanyard loop?

The very back of the rear toggle which stops the upward rotation of the rear toggle...

This will hit the frame rear just above the lanyard loop. Put the tape on the frame.

Marc

Was the it in 9mm originally?...if so,it needs a weaker mainspring...

Yes, she was originally in 9mm. Hopefully the reduced power spring makes her work well.

Peter..good point!

Fiocchi .30 Luger ammo is known to be underpowered... See if you can find a different brand of ammo, or start reloading...:thumbup:

Interesting. Who else makes ammo? Though underpowered, I can get Fiocchi for about $30 a box here. Can't say I've ever seen any other brands available.

Speaking of reloading, has anyone used 110gr. .30 Carbine bullets for .30 Luger? I can get 1000 Frontier CMJ Plated bullets for $84 + shipping. Everything else seems to be about double the price. And keep in mind, I live in Canada. I do not have the access to some of the amazing deals that american members have access to.

I have a fair supply of 110gr JSP bullets for my carbines, and have though many times about trying to develop 30 Luger loads with them, but, to date, have not done it. I fear that 110gr may just be a bit heavy for the Luger toggle system, but do not know for sure. I have looked and looked for any info on loading this bullet, but have come up empty.

I can look up the muzzle velocities of Fiocchi 30 Luger ammo, if you are unable to do so. I have some Western Super X 30 Luger ammo that is produced by Winchester. It is listed at 1220 ft/sec muzzle velocity and muzzle energy @ 305 ft. lbs. I believe that Fiocchi in in that neighborhood energy wise.


How does your barrel and receiver/barrel extension compare weight wise, to say an arty Luger?? They function o.k. with Fiocchi 93gr ammo.

The 1902 Luger Carbine has a foward assist spring in it's
forarm to help it go back into the battery poision and it has
a hotter load to recikle it,it also has a stock to take up the recoil. Food for thought.
Thanks,George

Then machine some compensator slots in that sight ring which will shoot jets of gas back at a 45 degree angle for an additional rocket boost!

:roflmao:

I think the compensator slots are a great Idea.
Thanks,George

I haven't seen any load info for 110gr. bullets either. I've found a number of listings from various sources for 100gr. bullets, however. It would certainly make things a fair bit cheaper for reloading.

Fiocchi lists it's ammo pretty well the same as Winchester; 1190 fps and 290 ft/lbs of energy.

I can't imagine it's any heavier that an artillery barrel. Below I've posted a blueprint for anyone interested.

We'll try a lighter spring and different ammo before I go that far :)

Thanks for including your blueprint... such details will assist others with similar aspirations of rebarreling their shooters...

I know of no other ammo available in the USA in 30 Luger but the Winchester and Fiocchi. Their power factors/velocities are well within range of error for either brand.

I feel that the modern 30 Luger ammo is down loaded somewhat to be sure not to explode any of the antique handguns using it.....like they do for 45 Long Colt ammo here in the USA. I have no way of knowing what the original muzzle velocities and power factors actually were out of a 4 in bbl, and the chamber pressures that they produced.

My pleasure! You blueprint CD, which I bought from you way back in October of 2010, was of immense help to my efforts. All the information for the threading and breech work was taken from your prints.

I do have more blueprints for the receiver support block and the action wrench if anyone is interested, plus a number of other prints relating to other parts and modifications. I have designed, though not yet machined and proven, a sight base to allow the installation of either a Micro sight or Bowen Classic Arms Ruger Flat-top rear sight for the toggle. If anyone is interested in any of this stuff I can either share it via PM or make a thread dedicated to the information.

First, be sure you're not limp wristing.

Winchester 30 Luger is under loaded and will not make the advertized velocity.

The Wolfe springs I've seen don't look anything like a Luger spring.

The 7.65 spring is different than the 9 mm spring. But cutting a 9 mm spring is NOT the way to go.

The action is operated by recoil which is determined by the load impulse. Pressure is not even considered in the calculation and has no bearing. The pressure should drop to zero before the action begins to unlock and has nothing to do with extraction.

The recoil spring MUST reliably close the action. The disconnector will allow the Luger to FIRE with the action not fully locked. That can get ugly. The recoil spring must be strong enough for reliable closing with the over weight barrel.

All this may lead to a hand load that is hotter than current factory offerings to get adequate slide velocity.

The action will take higher pressure than a SAAMI spec load with out turning a hair. The real danger in too hot a load is too much impulse leading to too high a slide velocity and cracking the toggle or abusing the linkage.

Interesting. So the opening of the toggle and ejection is solely determined by the rearward velocity of the breechblock? Cool.

So if the action is 100% recoil operated, and to my understanding it is on the short recoil principle, introducing a heavier bullet at at equal or higher velocity would improve cycling performance? Would subbing in a 110gr. .30 carbine bullet work? And if so, what would a suitable starting load be? I have ordered and received my set of Wolff springs, though have not had the opportunity to visit my pistol and install them.

If you go with a 110 gr. bullet, be sure you also use a slow powder. I am thinking Accurate #7. I think with this combination the pressure would be pretty much even all the way to the muzzle, thus insuring enough rearward inertia from the recoiling members to create a full cycle of the toggle and reciever.

Along with the above, you might want to get the LOWER power Wolff spring. I think its rated at 36lb.........................

Good Luck...........

Re : These addl blueprints would be very interesting and appreciated !!!
The bowen sight seems like better choice - but locked down and windage only probably best

thanks
Bill

DWM claimed the original 7.65 pistol load ran a 93 grain bullet out of a 4.5 inch pistol (not test barrel) at 1220 fps. I have reason to believe this claim is quite true.

Winchester claims 93 grains at 1220 fps from a 4.5 inch barrel. I have a LOT of reason to believe this is NOT true. I'e never got close to 1220 from any of several pistols with 4, 4.5, 5, or 6 inch basrrels.

The original carbine load ran around 40,000 cup and I believe the working carbine load also served as the proof load for the pistol.

SAAMi spec is 28,000 cup for the 7.65 vs 32,000 cup for ythe 9 mm. Hey guys! It's the same pistol in either caliber! Why down grade the 7.65?

Timing: The Luger unlocks fairly late compared to say, a 1911. The pressure will drop to zero before unlocking begins.

At a given velocity, a heavier bullet will provide more impulse. Keeping in mind there is a pressure limit.

for possible reference here is an original dewey custom luger base with the original micro sight replaced with a bowen sight

the original micro sight had a damaged front section from usage as elevation - was bent at the point of the elevation adj screw

thanks
Bill

Quite a deal of activity here in this last week. I have been out of the country for the past week, but have been watching the thread progress via my email notifications on my phone. I'm definitely going to try loading up some 110 gr. loads, just to see if I can get the thing to work. I have received my Wolff springs and will install it when I get a chance. The laws in Canada are... awkward for this, and I cannot posses my Luger until is gets reclassified from Prohibited to Restricted, which is apparently rather easy to do, so fingers crossed.

Bill/lfid:

Thank you for more pictures of the rear sight base. I plan on doing something nearly identical to that. How is it attached to the pistol? I see a roll pin there, but I cannot fathom what purpose it serves.
I'll shoot you a PM back soon. However, tonight is late and I'm weary from travel. Having said that, I am very interested.

Cheers all, and thank you for your continued interest in this project!

I, for one, am interested in how your development comes along with loading the 110gr jacketed bullet into the 30 Lugar brass. Please keep us informed.

Re : the Dewey rear sight base appears to be well soldered to a machined flat that removed the rear toggle original axle bump and sight. the front pin is the pivot point for the elevation on the micro sight/bowen eqivalent. the rear side "pin" near the soldered base line is actually a very small allen head screw that engages the elevation screw threads to prevent it loosening up from the toggle sight dynamics. problem in using elevation screw is that it likely fails - I suspect due to the bounce effect when the sight elevation springs get hammered by the toggle slap against the luger rear frame stop.
the Werle web sight has a reference that future target lugers would have elevation locked down and so elevation would be in the front sight. the pinned blade in your blueprint should allow variable height blades as needed - but the prewar colt woodsman 22 front sight method might be a better as allows adjustments.
VERY interesting project !!!
thanks
Bill

top view Dewey base
 

some more detail re the side lock pin and base design

A very nicely done rear sight.

Any further news on cycling and reliability for your pistol?

Nothing yet. I haven't had the chance to visit my pistol in nearly two months. Between Saturday overtime shifts and sickness, I haven't been able to muster the energy to make the trip out to my friends' place. I did, however, get my hands on one hundred each of 100gr. and 110gr. bullets, Hornady "half-jacket" and Sierra RNSP, respectively, and have 500 Starline Cases on order.

Interesting how the base is attached. I didn't expect it to be soldered on. Figures though, and could potentially be better than a dovetail, or other friction based attachment. I'll post my other blueprints later. busy busy.

My most reliable Luger is a 7.65 Para W+F P06/29 National Match with a 200mm pencil barrel. Just sayin'.

Re the function of the Dewey example I pictured earlier, I have not tested it yet - but plan to do so with the winchester white box 9mm in a few weeks - after go/no go check and another check for any visible cracks anywhere

the former owner provided a partial box of corbon type 9mm which he stated a gun shop had recommeded since Lugers need heavy loads etc. - apparently the corbon functioned ok for his test of at least 8 rounds - but the original micro steel sight had a bent body and the front pin came out in three pieces and the elevation screw was also loose - the original base seems ok

anyone have any Dewey luger test results ?
thanks
Bill

Here are my wrench plans:

The wrench head is made from 4140 Cold Rolled rectangular bar, 1" x 4". The handle is made of 4140 Heat Treated & Stress Relieved (HTSR, also Quenched and Tempered), received in Turned, Ground and Polished condition, and is 13" x 1.000" diameter. The handle has a 1" long by .751" diameter section on one end and is pressed into the body of the wrench. I also drilled and tapped a 1/4-20 hold and further secured the handle with a bolt.

What CAD program are you using??? :)

I'd be interested...I like to wallpaper the walls of my shop with prints... :thumbup:

+ 1 :thumbup:

It bears repeating that the German/Metric system does not readily translate to 'Yankee'/inch conventions...Example - 75% thread depth; round/flat thread peaks/valleys; thread angle; Metric/Yankee allowances/tolerances; etc...

The best blueprint is the part itself...