Front Sight Mod

[PhilOhio]

...just wanted to share with you fellas the interesting and accidental fix to a problem which had been driving me up the wall.

Several months ago, I was asking forum members for help in understanding why my newly acquired 1937 S/42 was shooting about 6" to 8" high at standard 50' target distance...shooting my reloaded cartridges which closely duplicated regular service loads.

Lugers are much more accurate than that. And no, this is not because they were calibrated for 100 meters. Firing dynamics of the pistol (including muzzle jump before the bullet leaves the barrel) are such that there is little or no 100 meter drop of a 125 grain 9mm bullet travelling at 1100 feet per second; most assuredly not 6".

Since drifting in a replacement front sight blade is something which can be done without permanently changing a good matching pistol, it seemed like a reasonable thing to try. Yesterday was the day, thanks to my Chinese bench top mini mill.

I've made a lot of front sights to correct point of impact on fixed sight handguns. Usually I epoxy a piece of cereal box cardboard to the barrel; shoot it on the range; use a scissors to trim it until groups are zeroed at 50'; measure this correct height cardboard sight and then make/install a metal blade. This time I just made a rough squared metal blade about 1/8" higher than my guesstimate of what would be needed; and with male dovetail to match the Luger barrel's slot. I started with a blade 11/32" above the flat on the front sight boss of the barrel.

I milled the blade .077" wide, thinking this was about as thick as it could be, to be useful in matching the width of the rear sight's "V" at the top; any wider, and I could not accurately center the front sight blade. And I did not want to modify the rear toggle link by widening and squaring the notch, as should really be done for a shooter.

For you ambitious guys who try things like this, I have a 12 volt D.C. to 110 volt A.C. inverter which I plug into my car's lighter receptacle. It feeds a speed controller for my Dremel tool, on which I mount an abrasive cutoff wheel; this because there is no outdoor power at my range, 2.5 miles from home.

Anyhow...shoot a couple, trim sight slightly, shoot a couple more; sight adjustment the hard way. But it works great.

After only two or three Dremel trims, I was dead on at 50'. And I noticed it had been unusually easy to get a good sight picture, unlike before, with the Luger's standard tapered blade.

THAT, it turns out, had been most of the original problem!

Back home, I contoured the new sight to look like an original, and used a Swiss file to put in all the little anti-glare grooves; blued it and drifted it into position to center shots, which had earlier been striking slightly to the left.

Then I measured the heights of the original Mauser blade and my new one. Huh? What's this? My new blade, which totally corrected point of impact, was only 1/32" higher, being 1/4" high exactly! How could this correct a point of impact difference of 6" to 8" at only 50 feet?

It was all in the width, substituting an untapered, squared blade .077" thick...instead of the skinny Luger inverted "V".

The human eye is no different than a camera lense. It cannot keep a rear sight, front sight, and distant target all in focus at the same time. The Luger sight system, with a rear "V" and thin inverted front "V" is the worst of all worlds; at least, if you want to see and hit anything. For our collector guns, it's fine.

So almost all modern arms manufacturers use a fairly wide front sight blade on guns that are actually expected to hit something. It makes it so much easier to center the blade.

After about age 40, our eyes' ability to focus at short range begins to drop off dramatically. With the skinny Luger front sight, about the top 1/3 of it becomes virtually invisible. It did for me. All I could see was the fuzzy lower 2/3, and I guess it was the top of that fuzz which I was trying to align with the top of the rear sight blade.

This new squared blade completely changes the gun's functionality for me, and probably would do so for most of you. Do any of you Luger experts know if somebody already makes one? If not, somebody should. And they should come in about 3 - 4 different heights, for differences among pistols and loads. It seems to me that there are enough fixed sight "shooter" Lugers out there, and enough people using them, that this worthwhile mod could be offered at a modest price, considering the ease of CNC milling of such a simple part...possibly just a minor dimensional variant of a sight blade already on the market; no need to reinvent the wheel.

Question for you seasoned Luger experts and collectors: Did DWM or Mauser go to the trouble of accuracy testing new pistols and equipping them with standard front sight blades of differing heights, to regulate point of impact and correct for normal production line variations? Seems like this would be the correct German way of doing things.

By the way: I found the German front sight blade notch, on my Mauser barrel, was tapered from right to left. Or maybe it was the blade's dovetail. But measurements suggested it was the notch. You can drift in an original blade from the right, but cannot drift it further to the left (beyond center) to correct left-of-center point of impact. Strange. With aftermarket barrels, the notch seems to be straight through, so you can adjust the front blade.

And also by the way: This week, after owning it for 40 years, I've been making adjustments on my minty 1917 artillery Luger's "fine tune" sights, to zero it; having made a fancy spanner and ordered another from Tom H. I don't think the screws had been turned since leaving the factory. I am mightily, mightily impressed by the precision craftsmanship which went into these. They work. The pistol is virtually a match pistol. And it was obvious to me that special tuning had also gone into the trigger pull which, for a Luger, is amazing.

I'm learning, or re-learning, how some of you have become so deeply hooked on these fine pistols; earlier, that is.

[davjed]

I built mine up last week using alumaweld epoxy. sanded it to shape and reblued with a marks-a-lot. haven't shot it yet tho.

[Thor]

Lugers can be incredibly accurate. This 30 Luger target was shot with .308" dia bullets which arent even really matched in size to the bore.

[Ingvarg]

Originally Posted by PhilOhio

...

The human eye is no different than a camera lense. It cannot keep a rear sight, front sight, and distant target all in focus at the same time. The Luger sight system, with a rear "V" and thin inverted front "V" is the worst of all worlds; at least, if you want to see and hit anything. For our collector guns, it's fine.

So almost all modern arms manufacturers use a fairly wide front sight blade on guns that are actually expected to hit something. It makes it so much easier to center the blade.

After about age 40, our eyes' ability to focus at short range begins to drop off dramatically. With the skinny Luger front sight, about the top 1/3 of it becomes virtually invisible. It did for me. All I could see was the fuzzy lower 2/3, and I guess it was the top of that fuzz which I was trying to align with the top of the rear sight blade.

Exactly the same problem I somtimes have, usually if the lighting is,nt good enough. The top of the front sight dissaper and I only see the lover rifled part of it.
For me, smoking the sights with a match and consetrating on focusing on the front sight usually fix the problem.

[PhilOhio]

Thor,

Thanks much for that pic of the target, along with the load info. I've just gotten geared up to reload .30 Luger for what I consider one of the all time best pistols ever made in that caliber, a mint '69 or '70 SIG P-210 soon coming to me from another board member and friend here.

Youre comments on bullet diameter stopped me, though. What diameter do you recommend? I'm set up to either cast them or swage jacketed bullets, so I could tailor my own dies to a precise diameter for the latter.

I guess that, inevitably, reloading this round will lead to one or more Lugers in that caliber. It seems to be the way life works.

Have you clocked that target sheet load? My Lee data shows velocities in the 1400 FPS range. This would be quite an accorate, flat shooting little screamer, with jacketed soft point hollow points. Yet they say the cartridge was originally considered too anemic for military use, so George Luger went to 9mm Para.

[Thor]

Seems like .310" is what I remember being the correct 30 Luger bore diameter. I think Hugh Clark has done tons of loading with the 30 Luger and would have a lot of info. Email him at hhclark@wildblue.net or perhaps he will see this and respond. No, I did NOT have a way to chronograph that load but it was really accurate. I once popped a Pepsi can at 60 yard with a 30 Luger the first shot which is really beyond my eyes at present. I had a great rest and the 6" Barrel helped. I guess I just get lucky once in a while

[Vlim]

How about using the squarer P38 front sight? Should drop right in.

[DavidJayUden]

Is the P38 sight taller? I ask because I have a Navy shooter that shoots WAY high (8-12" high at 25 yards). It would be nice to find one to start working with to get it down on the paper. If they are taller, what is a good source for them?
DJU

[PhilOhio]

Vlim,

BRILLIANT! If only I had known before making one from scratch. There was my P-38, lying underneath the Luger pile in the drawer. The P-38 (postwar P-1) blade is almost exactly what I made from scratch, but 1/32" higher. Dovetail looks the same. As you say, it should be a drop-in. Could have saved myself hours of milling machine work.

David,

The P-38 sight blade I measured is exactly 1/16" higher than the original blade on my S/42 Luger. That's a lot. It should lower your point of impact close to where you want it. Gun Parts Corp (Numrich's) should have it, among other sources. If it's still not high enough, the blade is thick enough so that a skilled TIG welder can build it up and let you dress it down to where the point of aim is correct.

Thor,

.30 Luger is looking better to me all the time...fast, light, and accurate. Lead bullets, held to about 1100 FPS with conventional lube, should do nicely, not lead the bore, and cause zero wear. With Alox, I'm sure they can be driven at full velocity without leading. Lyman says .308" to .310" for both lead and jacketed bullets. My RCBS Load database specifies .308". Lee gives no info for bullet diameter in their .30 Luger data sheet, which is strange. My main reference for dimensions is "The Illustrated Reference of Cartridge Dimensions", which shows a bullet diameter of .3095". I guess measuring or slugging a specific bore would be the only way to know for sure.

[Hugh]

Numrich has Mauser Rifle front sight "blanks" that can be modified. The Mauser and Luger front sight slots are the same.

Older Luger bbls usually run .310-.311, the new reproduction bbls have .308 bores. 308 bullets will work in the old bbls as the bases will upset enough due to pressure to get a good seal. You can use 32 cal .312 bullets and swage them to .3095, I found that swaging in one stage very difficult, it was much easier to do it in two or three steps, .311, .310, 309 and final bullet dia ended up @ .3095. If you are casting, cast or resize them to .309 and they will work in both diameter bbls.
Here are some loads for the 30 Luger;

[PhilOhio]

Hugh,

That's a beautiful piece of wood on that grip panel.

Thanks much. This project of reloading for the new (to me) caliber is looking easier and easier...for reasons some of you may be unaware. Lead bullet molds for .30 caliber are normally made to cast a bullet diameter of .309 to .310, with the expectation that they will be lubrisized to .308.

BUT...

The new Alox tumble lube liquids, such as that made by Lee and others, changes all that. If the cast bullet is fairly concentric and within several thousandths of your bore, Lee recommends that there is no need to size it at all. Just tumble lube a few hundred in a plastic bag with their liquid Alox, let them dry in the open overnight, and load and shoot them. They say it works best with their molds for bullets intended to be lubed this way, but that it works for any cast lead bullet. I have it, but have not tried the stuff yet.

So with just about any mold casting the correct weight of .30 Luger bullet, the diameter coming from the mold should be close to .310". Just tumble lube and shoot 'em. Sure beats the way I have done it with every other caliber for 40 years. Those bullets are going to be very close to the exact .3095" number in my primary reference book, mentioned earlier.

One problem I am running into is that I can't find a mold for as light a .30 bullet as this round requires. Closest I have or know about is the .30 Carbine bullet, but at about 120 gr., that's probably too heavy. .32 ACP is about the right diameter and 80 grains, which is a little light. Anybody use that? From the mold it should be about .310". Works fine in 7.65MM French Long, which is about the same bore. There's an odd one; I make the cases on a lathe from .32 S&W Long; not so hard, actually.

[Thor]

Checking my midway "Just about everything" catalog, looks like LEE makes two molds that you might consider, a 93 gr 1 radius ogive drops at .311" Mold # 311-93-1R, and a 100 gr 2 radius ogive drops at .311" mode # 311-100-2R on page 440. I like the weight of 93 grs which is pretty much standard, but I like the profile of the 2R ogive that is the shape of the 100 gr bullet. Both look like they would be superb. They come in 2 cavity and 6 cavity. Just food for thought. Hugh used to take a .312" jacketed bullet and run it through two or three cast bullet sizers to get it down to .309", I think after he ran it through the .309" it may have sprung back to .3095" or so. My brain is too old to remember dem detials!

[Hugh]

Ted,
Your brain doesn't have to remember, just read my post above!!!

[Hugh]

These cast bullets work well for the 30 Luger,

http://www.meisterbullets.com
32 H&R 94GR .312
Product Code: RB-32-94-2
Caliber: .32 H&R Magnum RNFP Weight: 94 GR Diameter: (.312)
(ask to resize them to .310 instead of .312)

http://www.magnusbullets.com
#205 - .30/.32 CAL, SWC FB, 100 GR., .309 DIA.

[PhilOhio]

Ted, Hugh,

Thanks so much for all this technical info. But I should kick myself in the butt. I've got so much fun stuff I lose track of it. This time I almost ordered that 93 grain Lee 2-cavity mold, which I discovered I already have...for my .32 revolvers. It's the perfect bullet, as long as you keep the velocity reasonable (I guess), or use Alox lube. In .32 S&W Long or .32 H&R Magnum, I've never driven it as fast as what .30 Luger may require. But the weight and diameter look right. It should be fine, tumble lubed as dropped from the mold. They say .311".

In that regard, I was recently rather shocked to measure some of Winchester's Silvertip bullets on their commercial loads, to see how oversize they are. I was trying to figure out why their out-of-the-box .45 Long Colt rounds were so much more accurate than anything I had been able to load for my Colt SAA. It has .451" grooves and .452" cylinder mouths. Lyman recommends .452" lead bullets. I made a sizing die to keep them at that out-of-mold diameter, only lubing them. Still didn't get Silvertip accuracy.

Then I find that the Silvertip bullets measure .454" and that is with aluminum jackets! Incredible. Jacketed bullets, .003" oversize, no indications of high pressure, and almost single-hole accuracy at 50'. I haven't quite matched it.

The point of all this is that, even if all the bullets mentioned earlier are fired tumble lubed and unsized in a standard .30 Luger bore, they should be safe, if not used with maximum powder charges. In fact, this may produce best accuracy. Anybody have experience with this sort of thing?

In a .310" bore, a concentric .311" or .312" bullet, tumble lubed in Lee's Alox, might be an accurate 1300+ FPS bullet producing no leading...and perfectly safe, pressure-wise.

[Hugh]

Phil,

.312 would probably be perfectly safe. Just be sure when loading the 312 bullets that you use the correct size expander button, a smaller one will cause you headaches!

[PhilOhio]

Hugh,

Yes, I've been through such headaches. If I have to make an expander, I like to have it about .0015" below lead bullet OD; gives me snug seating but doesn't seem to "swage" the bullet during seating.

Since my first go-round for this caliber (new to me) will be with a SIG P-210 not yet in my hands, I'm hoping that the Swiss did not do such a characteristically fanatical job on the chambering that rounds with maximum diameter bullets might be too tight in the neck area. Or maybe I'm worrying too much.

By the way...real long shot here...but might anybody know where I could get a 9mm P-210 barrel and the correct captive spring to go with it? I would like to have dual caliber capability, and know that all 210 barrels were hand fitted to each gun.

I'm headed to the nearby Camp Perry National Matches today, to ask the same question from some of the high end pistol vendors there on commercial row; really great when all these folks can be found in one place, once a year.

[Vlim]

Phil,

Getting a good (or new) P210 barrel may be a challege. SIG nor their follow-up Swiss Arms are making them at the moment and over here the price of used barrels has gone through the roof. The P210 is still pretty much the preferred sports pistol for military pistol competitions so it is expected that someone will start producing barrels shortly.

[PhilOhio]

Vlim,

That's pretty much what I was afraid of. But a possible new barrel source would be great news. I'd appreciate it if anybody turns up more on this, eventually. You'd think the Danes, or some other country which used the pistols, would have a spare barrel source which might be surplused out eventually.

Meanwhile, I guess I'd better become proficient at loading .30 Luger ammo.