doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Hollenbeck / Royal Gun Co Drilling #1518

Good afternoon, gentlemen! I hope everyone's weekend is going great!

As a collector of "working-man's" combination rifles, I've been on the lookout for an affordable drilling for some time. As a native West Virginian, I'd pretty much settled on a Hollenbeck gun.

And although I probably paid too much for it, I recently threw some money at an auction and won gun #1518, in 12ga full/full over .30-30. In retrospect, I probably paid too much, and after reading more on here and learning that damascus is indeed not actually a pipe-bomb waiting to happen, I probably should have bought a nicer damascus gun instead, as I've passed over several over the years. Hindsight, heh.

The shotgun barrels appear to be plain steel, and the engraving is light, with some wear in a few places. The shotgun bores are supposedly excellent, though the rifle bore is supposedly a bit dark. Externally, there looks to be the sort of bluing wear that one would expect from a well-loved 100+ year old gun, and none of the case hardening color remains on the receiver. The wood is surprisingly decent considering the other wear, except for a small chip out of the forearm. The top of the buttplate is a bit mangled and worn, as if the gun spent a lot of time propped up somewhere other than in a gun cabinet.

Unfortunately, it hasn't shipped yet, so I can't provide high-res pictures. I suppose I ought to have waited to post, but maybe I have "first drilling fever", heh.

I have a few dumb questions:

1. I assume that all of these guns had nitro-proofed shotgun barrels? I can't see any proof marks in the auction photos, but they are kind of low-res and the seller may not know what he is looking for, I dunno.

2. Is there anything in particular with these guns that I ought to check for before shooting it? I'd hate for it to violently self-disassemble!

3. Would it be worthwhile to re-proof it, or am I just being pedantic and ought to just shoot it?

4. I assume that all of these guns were produced late enough that they all have chambers no shorter than 2.75"?

5. Does anyone have a recommendation for mounting QD return-to-zero scope rings without mangling the gun up too badly? I was thinking maybe I could tap the rib and a screw on a section of picatinny rail, then remove it and install grub screws if I ever sell the gun.

6. I imagine a proper reblue job would cost more than the gun is worth, eh? Probably ruin any "collector value" as well?

7. If I have to send it off to a 'smith (and considering that I am just a poor dumb redneck who raises cattle, not some kind of wealthy oil-baron or something), who might you recommend? I am not sure that I'd trust our local guy with this gun.

Thanks, folks! I'm really looking forward to becoming part of the drilling community, and hopefully my Valmets won't get too jealous. Y'all have a wonderful weekend!

In the old factory ledger, serial number 1518 is on the first page of guns using Royal Gun Co. grade numbers. It is listed as a Grade 1, 12 x 12 x .30-30, with 28-inch Krupp barrels, weighing 7 pounds 7 ounces, half pistol grip, 14 x 1 5/8 x 2 7/8, sold 8-12-09 for $60 to J.B. Auchmuty. From the Royal Gun Co. catalog --

Welcome on your first posting Mr. Polecat, and congratulations on your new/old American Drilling. I never owned one of these guns, but I believe I can answer at least some of your questions:

1) The U.S. never had an official proof house as England and many European countries did. Some manufacturers here did their own in-house proof testing and stamped their guns with some mark to indicate they passed. Others did not. Your best option is probably an inspection by a competent gunsmith who specializes in doubles or drillings.

2) See no. (1) above.

3) See no. (1) above.

4) I would not automatically assume anything. including chamber length. When you have your gun inspected by a competent gunsmith, ask him to measure the chambers if you do not know how to do that yourself. Then you would want to use the appropriate low pressure and lower velocity ammo suitable for a 100 year old gun in order to prevent damaging the wood, breeching surfaces, and yourself, of course.

5) I myself would never recommend drilling and tapping the rib for any sort of scope mounting on this drilling. You paid up for this gun because it is a low production collectible vintage piece. Unless you wish to immediately lose hundreds of dollars in value by drilling a few small holes, you would do best to stick with your Valmet combination guns when you wish to use a scope.

6) Same as above. Unless your gun is quite abused and in desperate need of restoration to salvage and preserve it, any unnecessary refinishing is more likely to reduce its' value rather than enhance it. It may look prettier, but it will likely be worth much less to any collector. if you did decide to reblue the barrels, only slow rust bluing would be appropriate. Hot salts bluing should never be done on a gun with soldered ribs, as the salts will attack and loosen the solder. You'd be looking at around $300.00 for a decent slow rust bluing job, perhaps a bit more considering the extra work with the open sights versus a shotgun with only a bead.

7) I have purchased a couple doubles from Jerry Andrews in Moundsville, West Virginia, and have heard from numerous sources that he is a knowledgeable, competent, and fair priced double gunsmith. You might want to check him out and give him a call since he is relatively close to you. There are a couple guys on this site who collect these American drillings and will hopefully have more information to give to you concerning proper loads and the best choices for gunsmiths. I'm betting that none of them is going to encourage you to start drilling and tapping holes in one of these guns. Looking forward to seeing your pics when it arrives.

Mr. Polecat

Congratulations on the purchase of your Hollenbeck drilling. They are intriguing guns designed and made by one of the more talented gunsmiths of the era, Frank Hollenbeck. There is a thread from mid-February you might enjoy reading which was started by Ginge, who is having his Hollenbeck restored by a German gunsmith.

I have a Hollenbeck 12/12 over 25-25 Stevens, which took me a while to figure out since there is no marking as to what caliber the rifle is. With a 30-30, your Hollenbeck is much more practical than mine, and I suspect that you will find that it is fairly accurate and fun to shoot. By the way, the lever in front of the trigger guard is to cock the rifle, then you use the front trigger to fire it.

Good advice from Keith, and I have been looking for a gunsmith who will work on Hollenbecks. Since Jerry Andrews is from Moundsville, WV, he probably has seen and worked on a number of Hollenbecks.

If you can, post some photos of your Hollenbeck when it arrives.


ColinM

___________________________________________________

A little hard work never hurt anyone -- but why risk it?

I would encourage you strongly to use and enjoy your gun. I would also encourage you to go as lightly as you can on modifications and loads. I would shoot reduced recoil .30-30 loads if you can find them. I have shot my Hollenbeck a in 32-40 and 30-30 very casually. However in 25-35 I spent A LOT of effort working up a load and figuring it out. I found the gun to be VERY sensitive to presssure and what I thought were very light starting loads were too much for it in the long run.
I shoot it. I love it. I would never discourage anyone from using one but I hesitate to plunk factory loads in it. Even though we all think .30-30 is a light round.

Thank you Researcher for that catalog page. Note the Grade 1 was listed with "Crescent Steel" barrels. I have not previously seen that name. Was it listed in the Hollenbeck Gun Co. or 1905-1908 Three-Barrel Gun Co. catalogs?

Crescent advertised "Decarbonized Armory Steel" barrels from introduction of the Model 0 in 1897 until the mid-1920s.

Composition analysis by Optical Emission Spectroscopy (OES) showed c. 1900 Crescent �Wilson�s Welded Steel� to be Bessemer Rephosphorized Carbon Steel (similar to AISI 1017) with a Tensile Strength of 66,000 psi.

c. 1925 Crescent Fire Arms �Genuine Armory Steel� barrel with the �LLH� mark of Laurent Lochet-Habran was Rephosphorized AISI 1040 Carbon Steel with a measured Tensile Strength of 104,000 psi.

At the time 1518 was made, our North American ammunition companies were offering loaded 12-gauge paper shells in 2 5/8, 2 3/4, 2 7/8 and 3-inch lengths. Popular new shotguns of the time like Remington's John M. Browning designed Remington Autoloading shotgun and their John D. Pedersen designed Remington Repeating Shotgun and Winchesters Model 1897 were made for 2 3/4 inch 12-gauge shells.

One and 1 1/8 ounce loads were offered in the 2 5/8 inch shell and the 1 1/4 ounce loads were offered in the 2 3/4 inch and longer shells. In those days, the longer 2 7/8 and 3-inch shells didn't carry heavier loads than were offered in the 2 3/4 inch shells, but offered more/better wadding which many serious trap and live pigeon shooters believed important. The heaviest 12-gauge loads offered from the late 1890s to the early 1920s, 3 1/2 drams of bulk smokeless powder or 28-grains of dense smokeless powders such as Infallible or Ballistite pushing 1 1/4 ounces of shot produced higher pressures then modern SAAMI specs. The high velocity, progressive burning powder, loads were still thirteen years in the future when 1518 was built.

The Royal Gun Co. catalog states on page 12 --

Shot barrels are bored on the latest improved taper system for shooting all grades of smokeless powder.

I can't find any mention of shot barrel chamber length in any of my Hollenbeck, Three-Barrel or Royal Gun Co. catalogs. The hang tag for 1771 a Grade 2, 12 x 12 x.25-35, lists the load it was targeted with as 3 1/8 drams of bulk smokeless pushing 1 1/4 ounce of #7 1/2 shot, a very popular trap load until the ATA limited loads to 1 1/8 ounce beginning April 1940. Our North American ammunition companies were only offering that load in a 2 3/4 inch shell.

Despite what the Royal Gun Co. catalogs recommended 100 years ago, I would be very reluctant to feed one of these guns such a stout diet no matter what condition it was in. A lot of manufacturers claimed that their guns could digest the heaviest loads and kill ducks and geese at exaggerated and extreme ranges. And a lot of those guns were shot loose and beat to death and are no longer functional. There is advertising hype, and there is the test of time. The test of time never lies when it comes to durability of vintage guns. Marks_21 is one of the guys here who has a good deal of actual experience with these, and if he says standard .30-30 loads may be too hot for this design, I'd be inclined to follow his advice. I'd also stay with reduced shotgun loads to protect the stock wood from recoil damage. Recoil is a function of shot weight and velocity. Heavy loads at higher velocities produce more recoil. As for the stock design and the soundness of 100 year old wood, here's what gunsmith Brian Dudley had to say in another thread about these Hollenbeck designed drillings:



Brian Dudley has enough practical experience as a gun stocker to know which guns are vulnerable to stock damage.

The 1907 Three-Barrel Gun Co. catalog says "Damascus or Imported steel" for the Grade 0. The 1908 Three-Barrel Gun Co. catalog says "Crescent Steel" for the Grade 0. All of the Grade 0 listings in the ledger have either K or D in the steel column up through serial number 841. Beginning with serial number 842 we start seeing an S in the Steel column and still some Ds for the Grade 0. Beginning with serial number 1318 we begin seeing Ks in the Steel column for Grade 0s again as well as lots of Damascus barrel Grade 0s?!? In looking through these columns I found a W in the Steel column for serial number 851 which is listed as a Grade 5 which went to VL&A 6-24-07!! Want to see it.

Thank you.
Will do more looking into "Crescent Steel"

Thank you, sirs. Excellent information.

I will go as lightly as possible on modifications, though if the factory sights prove too difficult for me to see I may still have to figure out some way to put an aperture sight on it. Perhaps a period tang sight installed by a competent professional would not detract too much, if there's room.

I don't do any high volume reloading, but I do have a couple of single stage presses for working up accuracy loads, and a 12ga MEC press that I hardly ever use (somewhere; I've been planning to convert it to .410 but I never seem to get around to it). If all else fails and the chamber is < 2.75", maybe I can get that thing to load shells cut down to 2 5/8". It fares rather poorly at starting new crimps, though, and does much better on pre-fired hulls....

I guess back in this gun's day, the standard .30-30 load was still 160gn JSP... Over, what would be the closest powder still made, IMR3031? It will be interesting to work up a load that will work well with this gun's regulation.

So, it sounds like the jury is hung on whether it would be safe to occasionally put a 1oz slug in a shotgun barrel (something that I occasionally like to do with my 2-barrel combinations; we have weird laws about not hunting small game on the opening 3 days of deer season and other silliness). It sounds to me like the Krupp fluid steel was the strongest barrel that they offered, and that vintage shells were higher pressure than modern, so if everything is tight and the breech is on-face, it sounds like it would be safe (even if not very accurate in a full choke). On the other hand, 100+ year old gun, with 100+ year old wood.... But on the other-other hand, if everything is in good condition, then what could go wrong? ...... ... . Probably best to err of the side of caution, regardless, I suppose........

Thanks again, folks!

Edit: Thanks Keith. You posted before I'd finished writing this, heh. I'll be sure to stick to the lighter loads.

One of the guns I looked at a few years ago had a recoil lug installed. Must have been an attempt to prevent the furniture problems that you mention.

Again. I would never want to discourage. I have a nice process and recipe with a Mec 600 jr for 2.5 in shells if interested. And would shoot the rifle but try reduced recoil loads if you don�t reload and you can find them. If not let it rip I can�t imagine you will be putting a lot through it.

Well, I certainly don't want to smash the wood to bits, it's far too nice looking a piece of wood for that. This was a significant problem with the Savage 24s, too (which is why my crappy truck & tractor gun, a .30-30/20ga, has a wad of electrical tape wrapped 'round the wrist, heh). But it also cost beer money and was a "junk gun" to begin with, so....

The vast vast majority of my shotgunning involves clays with wimpy target loads. Then each year there's probably two dozen rounds of #4 heavy game loads killing squirrels for the pot and maybe a turkey (though I don't hardly like to eat them enough to have to bother with cleaning them up), a round or two of #5 bismuth, and maybe one slug every 2-3 years (outside of steel-ringing funtime).

I also like to load a 00 buckshot into a .30-30 case (it's oversize, but trims a ring like when loading a C&B revolver), over .7cc of Unique with a tuft of dacron to keep the powder back at the primer for consistency. Shoots about like a .22, but quieter and maybe not quite as far before dropping off, and is extremely accurate through that old Savage 24. I have to wonder if that would lead to squibs in a 28" barrel, though. Surely not, I guess, and I always look down the bore religiously anyway, just in case....

I bought a super rare (1 of 1) three barrel gun from Andrews last year. I wanted it bad, but It went back the day after i received it. For glaring issues that were inexcusable coming from a gunsmith. Pitted bores that were described as not pitted and ribs loose as could be at the muzzle. I dont know how you miss that one either. Unless you are looking at it in the dark.



I do not see the three barrel guns as the best option for installing scopes on. It would mean either ghetto jobbing something that will seriously compromising the functionality of it was a wingshooter. Or doing something extremely custom that would heavily modify the gun and be expensive. If you have to have a scope on a driliing, going with a German gun already setup for one on claw mounts would be a better option.

I've shot several rounds of skeet with my Crescent Steel barrel Grade 1 which shipped 4-6-1910, using my 7/8 ounce 1200 fps reloads in Remington STS hulls. Remington 209P primer, 16.4 grains of Clays, Remington TGT12S wad and 7/8 ounce of shot. This load lists at 6300 psi. After I got the gun I picked up ten boxes of .32-40 ammunition and some new brass, but here 19 years later I've still not yet fired the rifle barrel.

My two-part article on these companies was in The Double Gun Journal, Volume Thirteen, Issues 2 and 3. There was an article on a very interesting one of these guns fitted with a Miller single trigger in the Arms Gazette for September 1978, and one in The American Rifleman for June 1964.

Re: Sights (albeit a bit off-topic, haha) -

Although it doesn't come on and off very quickly, I really like the return-to-zero scope arrangement on the Valmet 412. Mine wears a 1-4x Leupold (though the .30-06 is a little better at taking advantage of that scope than a .30-30 would be). For wingshooting with it, though, I usually just install the double 12 or 20ga barrels instead. I really like the gun, but I think the iron sights on the combination barrels are just really terrible; huge and imprecise.

On my Baikal Sever, I removed the factory rear sight and cut a dovetail right at the back of the rib over the chambers, and installed a Williams screw-out aperture in it (just the little windage-adjustable piece that is standard on many of their sights; the front sight adjusts for elevation just like an AK-47 pin). It works well with the factory front sight. For most hunting tasks, I leave a medium aperture screwed in. For wingshooting, I remove the aperture and use the threaded piece as a ghost ring, which works really well (at least until I go to put the aperture back in and realize I've lost it somewhere lol). Maybe works even better than a mid-bead does for me. I'd have liked to use one of the Meritt adjustable apertures, but they're just too big to not interfere with closing the gun up. I had to remove ~0.003 from one side of the regular hunting aperture to keep it from kissing with the gun closed up as it was. Very close fit.

There was a Crescent Steel Co. in Pittsburg in 1908
https://books.google.com/books?id=SjJSAAAAYAAJ&pg=PA477&lpg

Hardware Dealers Magazine June 1908



The rifle barrel was likely Krupp Nickel Steel or Spezial Gewehr Lauf Stahl

Outing 1909 with the Royal SBT

Here are some period .30-30 loads offed by Union Metallic Cartridge Co.

Just for the record, though I suspect most everyone here knows it, the .30-30 did not originate as a black powder load even though the name indicates it. However it is also true that when Win introduced it in 1895 they named it the .30 WCF, not .30-30. Although not proven beyond doubt it is highly suspected that Marlin was the first to use the .30-30 name, not desiring to put a reference to Winchester on their rifles.

Although it has been much debated over the years Dave Scoville of Handloader/Rifle magazines published some data written by Winchester many years ago. They stated emphatically that the .32 WS was brought out with the intent of being able to use factory Smokeless loads of a power level similar to the .30WCF & to be reloaded using black powder to a power level similar to the .32-40. They did not deem the .30WCF to give satisfactory results when loaded with Black.Thus the reason for them bringing out two cartridges of so much the same power. It seems at that point in time there were many who desired this capability. As Black powder use became less & less the .30WCF won the popularity race of the two.

Brought the gun home today, finally. Very exciting.

Unfortunately the weather is too poor outside, and it's too dark inside, for decent pictures.

I am both pleased and disappointed at the same time. The gun appears externally to be in better condition than the pictures appeared. The bluing is really quite good for its age. However, there is a very tiny dent in one barrel (nothing to worry about I don't think, I shoot my model 1912 all the time with a /much/ worse dent) and the rifling at the breech end of the .30-30 barrel is quite weak. I am not sure whether or not it will be able to grab the bullets in time to get them spinning before they are going fast enough to just strip through the rest of the rifling... The usual-with-old-guns very shallow freckles in the shotgun bores, but they are really pretty good.

I guess we'll find out. :P Hopefully I can post some photos in a day or three.

Noce piece of wood on that one.

Well, I finally built up the nerve to test fire.

Winchester Extra Light 12ga, Winchester 170gn .30-30 (that's all I had).

Turns out I have either a broken firing pin or a weak spring on the left shotgun barrel/rear trigger (will not fire, just click, probably broken firing pin as there's no mark on the primer), and some pretty significant chamber erosion in the rifle barrel (shoulder excessively stretched and a ring at the base of the shoulder, maybe from too much pressure). My rifle firing pin always protrudes, too, and I've read something about a return spring there that tends to break, which has me wondering.

Hopefully some hand loads and creative spring hunting will make the .30-30 ok, but the left barrel problem is... a problem.

I guess I'll take it apart this Sunday and see what exactly is wrong. Did I read something about someone in Florida having bought up all the parts for these things some time back? Are they still around?

Well, don�t fret too much, I received my old gold #35 from the German gunSmith, (see my other thread) all three barrels fired, my reduced handload of the rifle (.25-25 Stevens) had high pressure signs, now my left shotgun barrel does not fire at all, no click, nothing, the rifle firing pin does come out but fails to fire the primer, it�s not the firing pin spring, the old girl is a little finicky, It could be a weak spring to the rifle hammer, but don�t give up,she�s easy to get into, and my German gunSmith (Tobi Nisse) is an expert now on Hollenbeck drillings, he will be visiting the USA again in July. The spring is easy to find, The wheeler screwdriver set I got from Midway has the special little tip that unscrews the firing pin screw. The width of my spring is 0.44 inches the height of mine is 0.84 inches but may be slightly short because it looks like a small piece broke off. Apparently you just Obtain a long spring of the proper width and cut it to size you want. I Have not found a source for Springs yet, because my second Hollenbeck number 236 (I got it from cherries Fine Guns) is missing the spring to the rifle firing pin, believe it or not. I actually got that second Hollenbeck in case I need to rob parts from it ,which I hope never to do. if you enter your Hollenbeck, take off the trigger guard first, then take the screws beginning towards the bottom of the stock and work toward the barrel, separate the action from the stock about an eighth of an inch, then slide out the trigger assembly, it�s really very easy. Interestingly the safety and the mechanics and other factors of the action are quite different from number 35 to number 236, no telling what changes were made by the time yours was built, nevertheless don�t give up, there have to be a lot of us in the same boat, we can figure this out, Worst case,ship it to Mobile,AL and Tobi can fix it,since he�s become the Hollenbeck gunsmith expert!! Also you might consider emailing Tobi directly,send him pictures and make your problem his problem, I do that regularly info@tobi-greener.de. Good luck!

Here is the peculiar .30-30 brass.

Mr. Polecat,
previously, cartridges that headspaced on a rim( or belt for that matter) often had the shoulder area too far forward in the chamber. Such chambers would still pass a "go" gauge and not a "no go". Your problem could likely be addressed by fireforming cases with a small load of "fast" powder like Unique, 1/4 sheet tp, grits as filler, and more tp to close it up. Once fireformed, set the loading dies to just "kiss" the shoulder. Then only use your handloads.FWIW in a drilling, you won't be limited to round nose or flat bullets.
Mike

Well,I love the toilet paper, grits idea and will try that with my reduced load 2525 Stevens for my Hollenbeck drilling
I�m so excited to find another use for grit�s ,and for those readers that don�t know what grits are: search �ode to grits� by Roy Blount,Jr,he speaks the truth

ginge,
I also sometimes use worn out polishing media for fireforming and eat the grits. Some people that are not cultured enough to have any grits, use Cream of Wheat.
Mike

I�d be curious the OD of the neck. That really looks out of proportion.

Thanks, everyone.

Yeah, the neck seems pretty large to me, too, but I've discovered that the battery is dead in my caliper and I haven't had a chance to go anywhere that sells stuff like that yet. A .308 caliber bullet falls down inside the neck easily, but I 'spect that's to be expected as the same happens with the fired necks of some of my other brass from the other .30-30 too. It does seem a little looser though.

Someone elsewhere suggested that it could be reamed to .30-30 Ackley Improved, too, if there is a burr in the chamber that the brass is flowing into. Though if I can make it work as-is with fireformed brass, I certainly don't plan to load heavier and I imagine the AI calls for heavier loads, so eh....

I think I read somewhere that paper-patched lead bullets shoot well from barrels with eroded throats. Maybe that could be an option if the chamber is eroded over-size. The rifling looks a little weaker back near the breech, but it's certainly not gone or anything, so I dunno.

At this juncture, I think it may be beyond my redneck head-scratching, and time to suck it up and make the 3 hour drive to the nearest gunsmith that doesn't suck. Maybe I ought to just get hold of that fellow mentioned earlier, though he's about as far away as someone can be from me and still be in the same state, haha.

I suggest you use cerrosafe to figure out what you�ve got ( I Did that with my .25-25 Stevens, it was fairly easy and inexpensive)
Agree with Marks21, out of proportion , it�s not 30-30 Ackley Imp, could it be 32 Special ( thought that was 30-30 necked up to 32 cal bullet)
Looking like a fun project,stick with it, I know you have grits in West Virginia.
By the way, thanks to this thread, I had a bit of a breakthroughwith my 2525 Stevens and my Hollenbeck drilling , I had the same failure to fire problem as mentioned earlier and thought my spring was messed up or my hammer not hitting hard enough, as advised,I jammed my primers as far up into the case as I could and ,lo and behold, with six test firing�s, four fired with the first hit with thehammer and the other two with the second hit. I�m in business now, I�m going to load the reduced load IMR 4227 with toilet paper and grits and have a blast !!
If I get a decent grouping I�ll share it and then I�ll eat some grits, I wonder if anybody looked up Roy Blount, Jr: �song to grits�as I suggested, it explains a lot

Hmmmm, well it is definitely not bored to .35-30 (a .357 bullet is a good bit wider than the case mouth).

Still haven't made it to town for a caliper battery lol.

I think .32 Winchester Special might be a good guess. I am still pretty dubious about that ring on the brass, though.

I guess I will see about fixing the left shotgun firing pin myself. Haven't taken it apart yet, but depending on what the right-hand one looks like maybe I can use it for measurements to turn a new one for the left barrel. Then I'll leave the chamber casting and any potential reaming for a real gunsmith...

Mr.Polecat,
Leave any reaming to a gunsmith( I recommend no reaming),but you should be able to make a chamber cast yourself. A .308" bullet should drop easily in a fired 30-30 case, if it won't, something is wrong. The old 30-30 chambers are usually pretty generous anyway. Slug the bore, a 30-30 will be around .308", a 32 Win.Spec. .321-.322".
Mike

I think the suggestion of a good side-by-side gunSmith is a good one( I bet when the gun is clean inside the action, other than maybe replacing the small spring that retracts the shot gun firing pin, that everything will work fine, and I think you�ve heard our suggestions about making a cast of the chamber and bore It�s easy,and will give you your answers
good luck in the end you�ll be glad you have a Hollenbeck drilling !

Given that there is a fireformed case available, I submit that slugging the bore would be more informative.
Mike

Weeeelp...

The fired case mouth ID measures ~.315-320
The fired case mouth OD measures ~.345-350

The bore at the muzzle measures ~.305. The caliper I used is only accurate to about 0.005, so I assume that's a pretty solid bet on the bore still being .308. If I measured it accurately, which is kinda questionable IMO.

Hmmmm. The OD of the fired case neck is pretty close to what .32 WS ought to be. I find it to be extremely difficult to measure bores and chokes accurately with a caliper, so I reckon I need to dig up some buckshot and slug it like you said.

You are right that it is hard to measure small IDs with calipers, because of the curvature and need to hit dead center. I am usually .001-.003" off, when compared to using small hole gauge and mic. A slug can be hard too, if the barrel has uneven number of grooves.
Mike