A friend picked up a 16x16x unknown rifle caliber by this retailer. It has some type of underlever action. Should I pursue more information on this gun for those interested here?

YES!!
Please take a dial indicator and measure the inside rough
diameter of the rifle barrel
Thanks
Mike

OK will relay and try to get good pics of the proofmarks.

[img][IMG]http://i91.photobucket.com/albums/k283/Halpics_bucket/Greenersafety_zps1d3e69c3.jpg[/img][/img] [img][IMG]http://i91.photobucket.com/albums/k283/Halpics_bucket/AdolphLoesche_zpsc8743bab.jpg[/img][/img] [img][IMG]http://i91.photobucket.com/albums/k283/Halpics_bucket/Barrelflatsleft_zps67e58df9.jpg[/img][/img] [img][IMG]http://i91.photobucket.com/albums/k283/Halpics_bucket/Barrelsleft_zpsa7fadd2b.jpg[/img][/img] [img][IMG]http://i91.photobucket.com/albums/k283/Halpics_bucket/Barrelsright_zps5a7b0f39.jpg[/img][/img] [img][IMG]http://i91.photobucket.com/albums/k283/Halpics_bucket/Barrelflatright_zpsa6e44e8c.jpg[/img][/img] [img][IMG]http://i91.photobucket.com/albums/k283/Halpics_bucket/Actionflatleftsie_zpsb9946c94.jpg[/img][/img]

Hope these will do of the Loesche.

I believe the rifle caliber will be a 9.3x72R

12 GAUGE, yes check if a 12 gauge hull will fit the chamber

And I would say the 12 gauge chambers will be shorter than 2 3/4
and should be measured.

http://www.ammunitiontogo.com/index.php/cName/rifle-ammo-93x72r

So why are the barrels marked 8.8mm?

12 ga 2 3/4" fit each chamber nicely.

What do the proofmarks tell you Skeet?

Hal,
My security won't allow me to open the photos, saying the "halbucket" has Malware in it,so I couldn't look at the proofs. A 2 3/4" shell will chamber in the short chamber, because the crimp hasn't folded out.Once fired, the crimp will fold into the barrel and constrict it.Whether this is harmful or not is a big point of discussion. If the barrels are marked 8.8 mm, this is the bore diameter, not the groove or bullet diameter.The actual groove diameter in different 9.3x72Rs vary a great deal.Since I couldn't see the proofs, I didn't see if the case length was shown.There were several different 9.3 mm cartridges with different case lengths.
Mike

When in doubt do a chamber casting.

The 8.8 indicates a 9.3 bullet in the 8.8 rifling
As KY Jon says a chamber cast is a great idea

The fact that unfired 2 3/4 ammo fits the chamber is no
indication of proper chamber length, measure!

I am pleased you discovered it was indeed a 12 gauge

Study here
http://www.shotguns.se/html/germany_1890-1945.html

Nitro proofed both rifle and shotgun

Fun thread, thanks for sharing

Mike

Have you located the date stamp?

730 or 7.30 or 7/30
1922-1939 Date mark, in this case July 1930.
Can be used from 1912 but was not a legal demand before 1922.

With the 2,2g G.B.P. / STMG stamp and the mm mark it has mixed stamps so it must have been made fore or aft a few years centred around 1912. Loseche typically peddled upper rung/quality offerings.

Kind Regards,

Raimey
rse

I have an unmarked drilling with an 8mm rifle barrel that has this same type of marking for the powder & bullet, IE; 2grG.B.P / St.m.G. Its caliber marking however is 172.28/59. Other than the 59 all other dimensions check out for the 8x58R Sauer. It bears a proof date code of 2.07 / 690. Unfortunately from 10" to 13" from the breech the entire right hand wall of the right barrel is missing, from top rib to side rib.
A Hammer Drilling by Miller & Val Greiss has a 9.3x72R rifle barrel under. It is marked K.m.G / 12.7gr for bullet only. Caliber marking is 8.8m/m / 72. Proof date is 6.13 / 240.
Both have regular 65mm, 16 gauge chambers. Both are Nitro Proofed for both rifle & shot barrels. In both cases the "m" for Mantle in the bullet designation appears to me to be lower case, as it does on this example.

Der Ami Skeetx kindly opened the images I supplied. Except for "85" followed by an upside-down "U" just forward of the forearm clip I could not find any other proof marks or codes than the ones shown. Where should I look for a date stamp? Its 2 3/4" from the breech face to start of the cones.

Adolf Loesche, Hoflieferant - Magdeburg had additional outlets/satellite locations and with different advertising:
Hof-Büchsenmacher, etc.

http://www.doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=267712&page=all


"An Adolf Loesche opened his shop at Koelner Strasse 13, Magdeburg, in 1873. Son Gustav Loesche took over in 1905. In 1916 Waffen-Loesche, Magdeburg is listed at Wilhelmstrasse 13 (street renamed?). In 1916 he bought the remains of the bankrupt Stendebach & Co., Suhl. He closed this Suhl branch in 1926. His branch in Berlin is documented post-WW1 only, 1925-1941.
The Adolf Loesche, Grosse Packhofstrasse 21, Hannover branch was opened in 1919, together with A. Helmuthauser."

Kind Regards,

Raimey
rse

Hal,
I saw where Skeetx opened the images, but they also won't open on my computer,where the image id should be is a block with a red x.If there was a date stamp, it would be near the caliber stamp.The lack of proof marks(as far as I can see w/o photos)indicates it was made before the proof law.This in itself would date the gun(likely 1892 or before).On the other hand, if it is marked with 8.8, this would be part of the normal proof marks and could indicate manufacture during the transition period before early 1893. I am disadvantaged by not having access to the photos.For practical purposes, the 2 3/4" would be from the breech face,but would be difficult to measure w/o a guage.Conventional measuring tools can be used for comparison, but don't expect a precise measurement.Anyway, there is little doubt that the gun is "short chambered", unless it has been opened up.This is based on the appearent age.Of more interest would be the rifle caliber,a chambercast is still needed to determine the precise 9.3 cartridge.
Mike

Too bad Mike. Is there any way I can change my photos to eliminate the infamous "red X" problem? I think is has something to do with codecs that I know nothing about.

The way I measured the chambers was to look down the illuminated barrel and put the corner of a piece of metal at the point where it looked and felt like the cones began. I know this is very crude. The cones look quite dark compared to the chambers and bore...a sign of lengthening?

Hal,
Raimey kindly emailed the photos to me. The gun does have proofs.The use of both powder and bullet(steel jacketed bullet) together with the lack of case length indicates it was proofed before the 1911 improvements were implemented in 1912.The bore diameter being shown in mm rather than gauge indicates it was likely close to the implementation date. The nitro proof and steel jacketed bullet,makes it more likely that the chamber is 9.3x72R, but I would still recommend a chamber cast.BTW the crown W on a shot gun barrel means the barrel is choked. The crown U is the view proof, which is a detailed inspection. The shotgun caliber(ga) shown in a circle w/o a "70" next to it indicates it was chambered for the standard length shells, which would have been 65mm.Sorry for the confusion.
Mike

Hal;
I habitually measure shotgun chamber lengths in essentially the same method you describe. I use a 6" flexible steel scale & slide it along the chamber wall until its corner touches the shadow of the cone as you described, then just read the measurement on the scale. I have "Definitely & Absolutely" in spite of what some may tell you, found instances where this was more accurate on older guns than using a chamber gauge. This was due to the chamber diameter being slightly smaller than the "Modern" gage thus causing the gage to stop short in the tapered chamber.
Understand the shell length is determined by its "Fired" length. Due to the amount of case used in making a fold crimp even a 3" magnum shell would ordinarily enter a 65 mm (Aprox 2 9/16") chamber with no resistance, But should not be Fired in same.

Many thanks for all the information. Can I grease the chamber and use plaster of Paris (with a good cleanup afterwards) or should I buy some cerrocast or whatever its called? Source for same?

Hello
One way is to use a chamber gauge
.730 is the proper diameter for 16 gauge

Or you could measure a majic marker, mine measures .725 and add a layer of masking tape to make .730.



Stick the butt end of the calibrated majic marker into the chamber and see how far it goes in

Let us know what you find out
Mike

Hal,
Some people use parafin( avaliable in canning section in gro.store)as a quick chambercast and this would be better than plaster of paris.When I was a young lad,melted sulfur was used. Of course,cerrosafe is best(it is more precise), but parafin will indicate case length and which case head family the cartridge is in.This is for the rifle, others have addressed the shot shell chambers, don't forget it was proofed for 65mm shells.
Mike

Its a 12 ga Skeet.

Thanks Mike. I wonder if my duck stripping wax would work. I've poured lead in muzzleloader barrels before to make lapping slugs.
Maybe I can use the wax in the shotgun barrels also?

Will let you know when I get back to ND. I'm in MN now with the kids.

OH. Yes, The 12 gauge diameter of interest is .795

After coating with Rig grease, I measured the length of the shotgun chambers and forcing cones and the diameters of both bores with the poultry stipping wax that I
use on ducks. Twelve gage shotcups made handy bore plugs. It looks like the 12 ga.
chambers are 2.5 in. (60 mm) long, with a 0.008 in. taper from the 0.806 in. base to 0.798 in. at 60 mm. Bore diameters of 0.728-0.732 in. are reached about 3 cm. ahead of the chamber. I had a very hard time pushing the rifle chamber cast out of the barrel, so switched to paraffin that came out with a few stout taps on a 1/4 in. rod on the oily cloth plug.

Rifle rim diameter is 11.6 mm. and the 75 mm. case tapers from 10mm at the base to
9.3 mm at the neck. The forward third of the chamber seems to be nearly cylindrical. Traces of rifling first appear at about 80 mm. Throat erosion may have occured as a uniform bore diameter of about 8.5 mm. is not reached until about 90 mm. or 1.5 cm ahead of the chamber.

So were Austrian shotguns ever chambered 2 1/2 in. and can my measurements
help determine what metric cartridge this rifle is chambered for?

[img]http://http://s91.photobucket.com/user/Halpics_bucket/media/shotgunchambers_zps4127bc7c.jpg.html[/img]

[img]http://s91.photobucket.com/user/Halpics_bucket/media/rifleclose_zps0b52baa5.jpg.html[/img]

[img][IMG]

http://i91.photobucket.com/albums/k283/Halpics_bucket/shotgunchambers_zps4127bc7c.jpg[/IMG][/img]

hope one of the above work for the shotgun chambers

For Hal:

Hal
Yes for the rifle caliber
I would suggest Cartridges of the World as a valuable tool

One of the older cheaper ones would work just fine

http://www.ebay.com/sch/Books-/267/i.html?_from=R40&_nkw=cartridges+of+the+world

PM me if I may be of assistance

And I would certainly investigate the 9.3x72R cartridge
http://www.cheaperthandirt.com/product/61944

Mike

9.3x72R specs

neck .385, base .427, rim .482, length 2.84, ctg length 3.27

There is a 9.3x74R but this should be too large for the chamber and also
not made in the time period of your firearm.

Here is some other reading of interest

http://castboolits.gunloads.com/showthread.php?75108-9-3x72R/page2

16 in circle shotgun caliber 16/65
16/1 full choke
Letters are manufacturing markings to allocate every step to a certain armorer
118/35 stands for the caliber of the rifle barrel 9.3x72R (according to the Reichsgesetz)

The weapon was proof shot with smokeless and ‘Schulzepulver’ new type, proof house Suhl
1905 was the change to smokeless

The sequence of powder is:
1880 M71 military powder
Around 1895 ‘Schulzepulver’ civil market
1905 smokeless
Therefore 2,5 g Sch.P. stands for 2.5 gram Schulzepulver with 29.3 gram lead bullet
2,1 gr B.L. stands for 2.1 gram flaked powder Stmg stands for steel jacketed bullet…”

if I make a rifle chamber cast with wax what is the procedure?

Hal,
I'm still having trouble with photos, but will do as well as I can. In this type chamber it can be hard to see where the case ends and the lede starts.If the 75 mm case length is correct, it would be a 9.3x75R.This cartridge is in the class of 9.3x72R,and the case head is in the same family.To get 9.3x75R cases you have to trim 9.3x82R cases, which are expensive.It is my opinion that you should just use 9.3x72R ammo and reload the cases.The 3mm difference in case length won't make any practictal difference, but the difference in cost and convience will.
Mike

Pod as you can see I merely blocked the shotgun barrels with shotcups. Then I made a paper funnel and poured the melted stripping wax in to the breech face. I melted it in a long narrow clear glass jar over my gas range. You have to add a bit at the end as it tends of hollow out from the top down.

The paraffin worked much better as it is harder. I just plugged the barrel with a small piece of greased cloth. For greater pouring accuracy, I held a 12 ga plastic shotshell by the base with vice grips, poured the wax into that, and then carefully filled the rifle chamber. The paraffin also dishes down as it cools so you have to add a bit more at the end. I pushed the shotgun plugs out with a dowel and the rifle plug out with a soft iron rod.

With all the fine information the members here have provided, I am going to try and write up a description of the drilling and will submit it later for editing.

I can't get Skeettx's html file to open on this computer, but I did once on my other one. I'll try later.

I still need to know what the Crown over N means as well as the words Hoeflieferrt and Fernrohrmontage. I assume this gun was made in Germany, likely Suhl, correct? Did Loesche make any firearms in their shot or only edged weapons or cutlery?

Crown over N + the rest of the data
Used in conjuntion
See proofmark item #19

1891-1912
Nitroproof for rifled barrels

Stahl Mantel Geschoss (Steel Jacked Bullet)

Hoeflieferrt = by appointment

Fernrohrmontage = scope mount

Mike

p.s.
K.u.k. Hoflieferant = Royal warrant of appointment

Thanks. So the gun was originally proofed for 2.2 gm black powder (G.B.P.= German Black Pulver?)and later proofed for nitro in all barrels as evidenced by the crown over N on the rifle barrel and eagle and "nitro" on both shotgun barrels?

I really appreciate all the help. I would like to have the below edited for before I send it to the owner:

Of German manufacture, this drilling has two 12 ga. barrels chambered for 65 mm long cartridges side-by-side above a rifle barrel chambered for the 9.3 mm x72R cartridge. A single extractor serves all three barrels. The arm was sold by Adolf Loesche, Hoflieferrnt "by ppointent" of Magdeberg, Austria. The Loesche firm, opened in 1873, specialized in fixed blade weapons and telescope mounts. Loesche also had outlets in Berlin and Hannover. World War II brought an end to the business.

The action is an underlever type with double underbites and Greener crossbolt. A Greener side-safety secures the shotgun barrels. The rifle barrel employs a tang safety for the
adjustable double-set triggers. Gold cocking indicators for the three barrels lie forward of the tang safety and behind a finely stippled area likely meant to reduce glare when shooting. An adjustable sight with single folding leaf is mounted on the finely file-cut rib of the 27 1/2" barrels. A small amount of engraving is found on the bright finished action, underlever, trigger guard, and cartridge trap located behind the rear swivel. The rather straight grained stock has a finely checkered semi-pistol grip with a cheekpiece and hard rubber buttplate.

The action, both shotgun barrel flats, and the rifle barrel are stamped with a crown over a "U" indicating view proof, a detailed inspection. A crown above a "W" stamped on the shotgun barrel flats indicates choke boring. Both flats are stamped with a circled 12 with 13/1 underneath showing that both barrels are 12 ga. and full choked. Both barrels are also stamped with an eagle followed by "Nitro" indicating nitro powder proof.

The rifle barrel is stamped with a crown over an "N", the mark used for nitro powder proof in Germany from 1891 to 1912. A stamped "2,2 g G.B.P." shows the first proof prior
to 1911 was for a load of 2.2 gm. of black powder. The stamped "St. m.G. 8,8 mm" shows the proof was with steel jacketed bullets and that the barrel was bored to 8.8 mm., the
standard for 9.3mm bullets.

No comments so OK I guess.

Now the bad news. The forearm is missing. Too bad as its such a pretty thing in overall very good to excellent condition and would be fun to hunt with. Does anyone know a machinist who could make a foreend? Looks like an A&D lug, and the iron would be very simple as it cocks with the underlever and there are no ejectors.
[img:center]http://s91.photobucket.com/user/Halpics_bucket/media/001_zps0cf9886a.jpg.html[/img]

[img:center]http://s91.photobucket.com/user/Halpics_bucket/media/002_zpsb716724a.jpg.html[/img]

Hal,
Maybe Dutchman Wood Works (www.dutchmanwoodworks.com )can help.I recall (from either "Der Waffenschmied"or "Waidmannsheil")that they replaced the missing forearm for another German Gun Collectors Assn. member.I happen to have a 12 ga underlever drilling with a cracked frame that I planed to sell for parts, but you wouldn't likely have a use for the rest of it.
Mike

Thanks Der. I emailed the Dutchman. I think the chances of your forearm having the same width, radius at the knuckle and same distance to the latch from it are very slim. I'll contact some of the restoration specialists that advertise in DGJ to see what they have to say. Maybe some of them follow this board.

Hal,
Just for info in your research,mine is a 12ga,Meffert,underlever, hammer gun.It has a good forearm, good locks with both hammers, good trigger plate(set trigger doesn't hold, most have been misadjusted).Barrels have been brazed together at muzzle(can be used for "hakenstuck"to line for extra barrels or replacement barrels on other drilling.Missing lever and other parts for barrel selector. The stock is homemade and may not even be good for firewood.
This is one of the plain Mefferts, so should be easy enough to match engraving on another gun.
Mike

Note that the 12 in a circle is the nominal gauge for which the gun is chambered. 13/1 is its actual bore size, in this case meaning it will accept a 13/1 (.710") plug gage to a depth of about 9" (22CM if I remember correctly) but will not accept a 12 gage (.729") plug. Your actual amount of choke is not marked.
118.35 is a gauge size based on the same formula as the shot barrels. This indicates a size of .340". From only limited experience with these "Gauge" size markings on rifle barrels it seems these were made in increments of .010", thus the 118.35 mark would show it would take a .340" plug but not a .350" (108.49 gauge). For a 9.3x72R (.364") bullet size the bore is most likely very close to the .350".

In my experience with those marked 118.35, the groove diameter usually around .358-.359".This makes finding bullets pretty easy.
Mike

Thanks Miller. I got confused when Skeet said 16/1 was full choke. Will change description accordingly. So it looks like the barrels are both cylinder bore.

Woodsman kindly informed me that the gun was made by E. Schmidt & Habermann in Suhl.

Looks like the paraffin method is accurate Der as I measured .358 which equals 8.6mm groove diameter.

Sorry Hal

Did not mean to mis-lead, just posted the info about the 16 gauge gun in this article

http://castboolits.gunloads.com/showthread.php?75108-9-3x72R/page2

Mike

On the proof marks Crown/G denotes a Rifle barrel; Crown/S denotes a Shot barrel & Crown/W denotes a Choked barrel. If choked the Crown/W will e in addition to the Crown/S & simply denotes a choke with actual amount not specified. Can be anything from .2 mm (.008") on.
When the poster on that other forum stated the 16/1 meant that barrel was full choked he was simply in Error. 16/1 denotes a size of .669" which is .007" larger than a nominal diameter of
.662" for a 16 ga so quite obviously not a choke size for a full choked 16ga.
Hal if the gun in question has a Crown/W on either barrel then that barrel was not Cylinder bored, but choked to some extent which only measurement can determine. If it is cylinder in one barrel & choked in the other then only the choked barrel should have the Crown/W mark.

2-piper,
Actually,a crown G doesn't actually mean it has a rifled barrel, it means it was proofed for a single projectile.This would usually be a rifled barrel, but the same mark would be used for those smooth bored guns intended to use bullets.If the gun has rifle sights and a smooth bore, it may not have been converted from a rifle as some may suppose.
Mike

Thanks. I read the other thread in Boolits. Is the bascule the same as the knuckle or the surface where the forearm touches the action?

So is the nominal size for 13 ga .710 and the 13/1 gage made .007 larger or do the increments vary by guage? I assume these gages are made to measure from the chamber so there would be no interference from any choking.

I also read about the French and German set triggers. This gun has the German type I guess as I can't move the front trigger forward a bit to set the back one. The adjusting screw is on the back of the front trigger. But I don't get much, if any, reduction in trigger pull when I pull the back trigger after the front.

Hal,
The set trigger on the drilling is a single set trigger. You push the front one forward to set the front one, not the back one.The trigger should not be set until right before you intend to fire the rifle barrel.If,for some reason, you don't fire the rifle after setting the trigger; open the action and touch the trigger to unset it(the safety can be on or off).My German gunsmith friend was of the opinion that it is more dangerous to carry a gun with the safety on, but the trigger set, than with the safety off and the trigger unset.Don't forget that the front trigger fires the righthand shot barrel also, and if left set can create a "surprise" if firing the shot barrel.
Mike

Mike;
You are of course correct the Crown/G denotes a solid projectile. The G in this case I believe is for Geschoss which loosely interprets to Bullet & not Gewehr for rifle. As the G is most often found on rifle barrels I tend to forget its exact meaning, thanks for the correction.
Hal;
The in-between gauges are set halfway between gauges, given to three decimal places with succeeding digits dropped, not rounded. The gauge sizes them selves are derived from a formula based on the weight of lead & are rounded to three decimal places. thus a 13 gauge is .710", a 12 gauge .729". .729" + .710" / 2 = 1.439/2 =.7195. A bore marked 13/1 thus will accept a plug gage of .719" diameter to the specified distance but not a .729" one. Its exact size could be anywhere between those limits.
In sizes 10ga to 4ga there were two in-between sizes which were marked as for instance 8/1 & 8/2. In this case each size was 1/3 of the space between the two gauges. The actual number then will vary according to the difference in size between two gauges.

I'm fairly confident that units were metric and might account from some difference?:



Schrot/Shot


Geschoss/Bullet





From Axel's contribution:

http://www.doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=213433#Post213433

Kind Regards,

Raimey
rse

Excerpt from page 231.

Fuzzy, but I read it and could be wrong on all:

12/1 - 18.6mm?

12 - 18.52mm

13/1 - 18.26mm

13 - 18.02 mm

14/1 - 17.

14 - 17.6mm

15/1 - 17.4mm

15 - 17.2mm

16/1 - 16,29mm?

16 - 16.51mm?

17/1 - 16.64mm?

17 - 16.45mm

Kind Regards,

Raimey
rse

Haven't run the numbers but "Modern Breechloaders" gives

12 - 0,729" - 0,720"

13 - 0,710" - 0,700"

14 - 0,693" - 0,690" - 0,680"

15 - 0,677" - 0,670"

16 - 0,622" - 0,660" - 0,650"

17 - 0,649" - 0,640"

If I remember correctly, both the Austrian and Brits used a solid projectile on the 1st pass and shot later if the tube was destined to be a scattergun. Not sure when or if the Brits ceased.

Kind Regards,

Raimey
rse

Thanks Der. That's how they work. Seems quite awkward to have to pull my hands either off the forearm or off the grip to get my thumb behind the front trigger to set it, but I guess that's the way it was built unless it is supposed to set with a lot less forward pressure than it does now. I wonder how the front trigger can be safely unset? The gold cocking indicator pin for the left barrel does not come up like the other two, and it looks like the tip of the firing pin is missing. Incidentally, one of the reasons I sold my Valmet was in one day sending a load of No. 4 lead at a deer and then whistling a 165 gr. Core-Lokt .30 cal. at a pheasant!

Thanks Miller for the great explanation of the plug gage concept.

Hal,
It shouldn't take that much pressure to set it,maybe it is adjusted so that it almost doesn't engage.I would try readjusting it and see if that works(note the adjustment screw doesn't have anything to do with the spring tension,only the engagement). I would set it with the thumb of the shooting hand.To unset it, the safest way is to open the gun and pull the trigger with it open.Since the safety doesn't affect the set trigger, it can be left on "safe".

Raimey;
As you said a lot of those figures were too fuzzy to read for certain. On some that I could they seemed to be an exact metric conversion from the English tables. On those you put a ? after; 12/1 should be 18.8, 16/1 is 16.99/17.0, 16 = 16.81, & 17/1 16.64/65. These figures are derived from using the English numbers & converting. Those with double readings are dependant on exactly when rounding is done. Slight variations can of course occur on the exact diameter used for a 1 gauge ball. I found it necessary to carry this to 6 decimal places & then as a sorts middle of the road use 1.669285" as the basis. Using this number every size on the English tables fits to the nearest .001" which is good enough for me. I have tried them in metric but this number would convert to 42.399839mm.
It is noted that the volume of a ball this size is very slightly less than that given for 1 lb of pure lead. Perhaps when these tables originated well back into the 1800's a method of forming a pound of lead into a ball was used which gave it a slight compression. What is a bit amazing to me though is that even though all this had to be done by "Hand" & involves cubes & cube roots is that all these years later I can set down with a pocket calculator & fit it "Exactly" to that .001".

Der is the top (slotted for screwdriver I assume) of the trigger adjustment screw supposed to protrude a bit or always lie below the surface? The threaded hole is extremely small and I would have to try and bend my smallest screwdriver or perhaps grind down a tiny Allen wrench to get in there. Perhaps the screw is missing as I can drop a wire a full 1/4" down the hole before it bottoms out.

I'm not sure, but "bascule" seems to be the same as what we would call the convex outer radius of the hinge or knuckle where met by the concave surface of the forearm iron.

Hal,
The screw should be above the surface and in my experience is not threaded to the end, so it can't be screwed below the surface.It seems that yours is missing(if you are lucky) or twisted off below the surface(if you aren't).A proper screw above the surface can be turned by a thin blade screw driver.Your problem reaching the screw seems to be becaues it is missing or broken.If it is missing, a new one can be turned in. If it is broken off, the trigger plate will have to be removed and disassembled to remove the broken piece.I believe New England Custom Guns can help you with this, or maybe Turnbull.
Mike

Thanks. These guns are so expensive to work on I don't think the owner would be willing to put over $1,000 into it for a replacement forearm and repair of the set trigger/cocking indicator mechanism. What is this Loesche worth in its present condition?

Hal,
I'm sorry,I hardly ever give an estimate of the value of someone elses gun, even if I can hold it in my own hands. In this case, I know the gun has some problems.If you can't do the work to repair it,the value will be drasticaly affected.
Mike

Der Ami, I agree.
I posted a possible price, then ammended it, then deleted the posting. Just could not make up my mind and did not want to offend. Certainly as is, the price will be down.

Mike

Thanks Skeet. I guess the poor thing will have to remain unused or maybe shot without a forearm like I do with my Nitro Specials when hunting waterfowl.

As a follow up I reread the great article by J.C Munnell in the Autumn, 2013 DGJ. The Grundig over-and-under rifle he describes is remarkably similar to the Loesche. In addition to the unusual cocking indicators that POP UP when the barrels are fired and the "front only" set trigger, he mentions that the action is a Roux. Is there any historical information on this action?