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Kragshooter
01-04-2010, 09:35 PM
Anybody convert a 30-40 to 303 or something similar? My bore slugs out at .309 and shoots 30-40 really good but man o man is ammo hard to get. I have 80 rounds of good brass loaded up plus a box of new Win Silvertips. Just curious.

KCSO
01-04-2010, 09:50 PM
I don't think 303 will be any easier to get and the shorter neck will not be as cast friendly as that LONG 30-40 neck. IF I were going to convert I would almost look at 7.62X54 Russian as if I remember right that will clean up the Krag chamber nicely. The problem there is that 7.62 is loaded to a lot higher pressure and in a Krag will almost certinaly ruin a gun with full house ammo. I lucked out as a buddy who knew I shot 30-40 saw 6 boxes at a filling station in western nebraska on the shelf for $9 a box. He took them all and I got them for $12 a box. All W/W silvertip from the 70's.

Multigunner
01-04-2010, 10:21 PM
Anybody convert a 30-40 to 303 or something similar? My bore slugs out at .309 and shoots 30-40 really good but man o man is ammo hard to get. I have 80 rounds of good brass loaded up plus a box of new Win Silvertips. Just curious.

When I couldn't find a replacement barrel for my Wallhanger Krag Carbine, sadly long traded off due to its corroded bore, I considered having a .303 barrel made for it. Luckily I couldn't find a Smith that was set up to cut the threads for a Krag.

I later found that while the Krag handled it original cartridge loaded to circa 40,000 CUP with no problems , when the load was increased to 43,000 CUP in search of better performance a goodly number of bolts cracked or suffered setback of the lugs. So many rifles were damaged by the only slightly warmer cartridge that Springfield Armory began providing replacement bolts free of charge to civilian Krag owners who's rifles had been damaged by the higher pressure ammo.

The .303 cartridges up to the MkVI generated pressures not much higher than the Krag, usually in the 42-43 K CUP range. The MkVII generated 45,400 CUP which would almost certainly damage a Krag if used for any length of time, if not with the first shot.

Metalurgy of the Krag was still along the lines of the Black Powder era, heat treatment was not very consistent.
Some US Krags might handle the .303 with no problem, but just because a few might is not sufficient reason to believe that yours would.

European Krags seem to be made of sterner stuff, but they aren't considered suitable for high pressures either, even if both lugs make contact.
The lugs of the US Krag did not both make contact when new, the guide rib was left non bearing to act as a safety lug. If you see a US Krag with both lugs making full contact its almost certainly due to lug setback or a cracked lug.
Some Target shooters did modify their Krags by lapping to have full contact on both lugs. I expect these modified rifles, if head space remained close enough,
would handle the hotter 43,000 CUP loads okay.

Be happy you have a .30-40 that still shoots well, don't alter it un necessarily.

The Krag is a perfect candidate for mild Cast Bullet loads.
.309 is actually pretty tight for a Krag bore, .310 was common with these.

With mild loads you can make those cases last a long time if you neck size only.

Kragshooter
01-04-2010, 10:50 PM
Good info, thanks guys! Will stay a Krag and shoot cast mostly. I actually use it for a range gun as it is just too dang heavy to lug over these Colorado mountains. Maybe trade it for a lever, .35.

http://i439.photobucket.com/albums/qq113/ftlupton/IMG_0151-1.jpg

RayinNH
01-04-2010, 11:15 PM
If you load your own, you can use .303 Brit brass. After running through the 30-40 FL resizing die you wind up with a case that has a neck about 1/8" short of a true 30-40 case but with a long boolit like 311284, I've never noticed any difference in accuracy...Ray

Multigunner
01-04-2010, 11:31 PM
If you load your own, you can use .303 Brit brass. After running through the 30-40 FL resizing die you wind up with a case that has a neck about 1/8" short of a true 30-40 case but with a long boolit like 311284, I've never noticed any difference in accuracy...Ray

A case neck that much shorter than the chamber neck can cause problems, at least when jacketed bullets are used.

The Boers ended up with a huge quantity of short necked &mm Mauser ammo when buying up as much ammo as possible during their struggle with the British.
The odd sized 7mm Ammo measured at 7X53 rather than the proper 7X57.
The 4mm difference in neck length was blamed for a number of action failures.
The theory being the bullet would slug out to fit the chamber neck then strip a ring of jacket metal into the neck area, the next bullet would telescope into the ring and when fired it was like a double thick band of jacket the size of the neck trying to swage down into the much smaller throat.

The Boers found that by coating the bullet with a thick grease the blow ups could be avoided, but the British thought the grease (which turned an ugly green after awhile) was some type of poison and often executed Boers captured with the grease coated bullets. The grease may have carried dirt and such into wounds.

Using a well lubed cast bullet, which I would say is your practice may be okay, but I would not want to try jacketed bullets from a short necked case in a long necked chamber. Best to segregate the cases.

3006guns
01-04-2010, 11:39 PM
Remember the "good 'ol days".....about 15 years ago? A bunch of British P-14 Enfield drill rifles were imported with brand new, but drilled, barrels. At $25.00 each I bought two for the actions. I had an extra Springfield barrel installed and chambered for the .30-40 krag and the result is a nice short tough little rifle that will take some pretty stiff loads. I really think the brass would give out before the gun does.

Kragshooter
01-05-2010, 12:23 AM
Somebody wouldn't have a carbine stock and barrel band for sale would they? I would like to put this one back to that style for more of a brush gun for the black timber after elk.

Kragshooter
01-05-2010, 09:08 AM
I checked my favorite supplier for .303 brass last night and low and behold they had 30-40 brass, it's on the way as we speak. Think I will cast up some 173 gr flat points and when the weather allows I'm headin out.

45nut
01-05-2010, 09:25 AM
Remember the "good 'ol days".....about 15 years ago? A bunch of British P-14 Enfield drill rifles were imported with brand new, but drilled, barrels. At $25.00 each I bought two for the actions. I had an extra Springfield barrel installed and chambered for the .30-40 krag and the result is a nice short tough little rifle that will take some pretty stiff loads. I really think the brass would give out before the gun does.

I have one of those drill rifles with the hole in the chamber,, you say a "common" springfield barrel will screw in with minimal work?

mroliver77
01-05-2010, 01:33 PM
The pic of your gun shows my idea of a great hunting rifle. I cant imagine it being too heavy but then I have never prowled around mountains carrying all the necessities. I really like the 30-40 round especially for cast.
Jay

Bob S
01-05-2010, 02:11 PM
you say a "common" springfield barrel will screw in with minimal work?

Not hardly. A "Springfield" (M1903 or 03A3) barrel must be shortened at the breech about 1-1/2", rethreaded to fit the Krag action, and then rechambered/throated to 30-40. The amount of work is about the same as starting out with a commercial contoured blank. The reason that you see a lot of Krag sporters with ex-M1903 barrels on them is that the surplus barrels were readily available and really, really inexpensive when the Krags were released into the surplus market. I have a Krag sporter from the same time period that has a M1917 barrel on it.

Back in those days, in order to be called a "gunsmith", a guy needed a good lathe and mill, needed to know how to use them, and needed some engineering sense and skill on the target range. Those guys are very, very hard to find these days.

Resp'y,
Bob S.

P.S. Midway was showing Remington 30-40 brass as "available" yesterday.

45nut
01-05-2010, 02:18 PM
Actually my question was more directed to the P-14 drill rifle I have,, which I know to have square threads. Not many of those commonly found in my area.

Kragshooter
01-05-2010, 02:43 PM
It is a heavy gun and if you have ever shot an elk 2 canyons over from the pickup you will curse every ounce of it. It does shoot great, the stock was done professionally, inletting tight and perfect. Fits me like a glove, I bought it from a 80 year old who just couldn't hunt anymore. He was a delightful guy and Iloved hearing his hunting tales with the gun. This is the second group I shot with it.


http://i439.photobucket.com/albums/qq113/ftlupton/IMG_0156.jpg

Bob S
01-05-2010, 07:03 PM
Actually my question was more directed to the P-14 drill rifle I have,, which I know to have square threads. Not many of those commonly found in my area.

My apologies for not reading closer.

I have not done this, and I know that someone said it has been done, but looking at the drawings, it's going to be as labor-intensive as the Krag installation I described above.

Both have 10 TPI square threads, but the major/minor diameter of the Enfield threads is 1.125"/1.085", and the diameter of the torque shoulder is 1.325"

The major/minor diameter of the M1903 threads is 1.040"/0.990" and the torque shoulder is only 1.145" in diameter. The tennon of the Springfield barrel is thus way too small to just thread into the P14 or M1917 receiver without using a bushing. The whole tennon will need to be cut off and a new one turned and threaded to fit the P14 receiver. Once you do that, you end up with only .090" bearing surface on the torque shoulder. Maybe that's enough, but I wouldn't be comfortable with it. Given the cost and condition of M1903 and 03A3 barrels that are extant today, I would recommend just purchasing a contoured blank and go from there. Unless you are doing the lathe work yourself, the cost will be the same. Or you could purchase a pre-fit barrel from Pac-Nor and you could trade off some initial acquisition cost for a decrease in labor time and cost to fit it up. Pac-Nor prefit barrels are contoured to standard dimesions or your custom requirements and threaded for the action and long-chambered, so they still need to be chucked up and have the torque shoulder skimmed to fit the receiver and headspace, and the extractor clearance cut still has to be made once the headspace is correct.

Just my two cents, and worth exactly that ...:mrgreen:

Resp'y,
Bob S.

3006guns
01-06-2010, 12:16 AM
No, I owe the apology......don't know what I was typing. I had the work done a number of years ago and it WAS a blank that was installed, contoured and chambered for 30-40. Sorry, a bad case of CRS I guess! In any case, it made a real rifle out of a wall hanger.

It was really a shame about those drill rifles...a hole punched through the chamber on an otherwise good gun. I keep hoping one of the major distributors will locate replacement P-14 barrels so I can rebuild the one I have left. Faint hope!

Kragshooter
01-06-2010, 11:20 PM
Midway shipped 100 remington 30-40 brass to me today. This should last a long time with moderate cast loads using 2400 or Unique. I plan using the Lee 173gr flat nose cause that is what I used in my 336 with gas checks.

mroliver77
01-07-2010, 12:18 PM
I picked up a "sporterised" Krag a few years back set up as a carbine with Lyman peep and bead sights. What a slick little shooter. My nephew home on leave from Marine Corps gave it a workout while I worked up loads for it. He fell in love with it and wanted to buy it. I gave it to him. He likes the 311284 in it and wants to kill everything on the planet with it.:) Nice to see a young un apreciate a 100+ year old rifle.
Jay

Char-Gar
01-07-2010, 12:55 PM
Here is my current project. The stock is roughed in and now I am doing the final shaping and detail work. It is a rather plain grade of black walnut, I picked up on Ebay for $25.00. The action is a 1902 and the barrel is a new Remington 2 groove 03A3. I have had this barrel for years, and my gunsmith shortened the breech, rethreaded, chambered and laped the bolt safety lug to a tight fit on the receiver.

Judging by my progress, it should be ready sometime this year. I have two other Krag sporters that are cut down military rifles.

StarMetal
01-07-2010, 01:19 PM
Here is my current project. The stock is roughed in and now I am doing the final shaping and detail work. It is a rather plain grade of black walnut, I picked up on Ebay for $25.00. The action is a 1902 and the barrel is a new Remington 2 groove 03A3. I have had this barrel for years, and my gunsmith shortened the breech, rethreaded, chambered and laped the bolt safety lug to a tight fit on the receiver.

Judging by my progress, it should be ready sometime this year. I have two other Krag sporters that are cut down military rifles.

Hey I like that. Charger are you left handed?

Joe

Char-Gar
01-07-2010, 01:54 PM
Yep... I am a South Paw!

Multigunner
01-07-2010, 02:28 PM
Here is my current project. The stock is roughed in and now I am doing the final shaping and detail work. It is a rather plain grade of black walnut, I picked up on Ebay for $25.00.

That promises to be a beautiful rifle when finished.

I wouldn't worry about the grain being plain, you don't want much if any figure with a Krag stock, too much has to be cut away for the magazine mechanizm as it is so the wood must be plain grained and strong as possible.

I passed up a 1903 with C stock years ago because its beautifully figured wood had broken clean through in several places at the magazine well allong the lines of the grain.
I suppose it had suffered some really radical damage to do that, perhaps been in a saddle scabbard when a horse fell on it, or perhaps a vehicle wreck, but the only real damage was at the mag well.
Sometimes heavily figured wood can check fracture and decades later the cracks spread all the way through for no apparent reason.
By the time I got around to deciding to buy that 03 and try to fix the stock someone else had snapped it up.

Breakages arond the mag well seem to have been a problem for the Krag in service.

When I finish up the projects I'm working on now, which will take another year or three, I hope to pick up a restorable Krag of some sort.

The Krag is an action I'd like to see brought back as a modern reproduction sporting rifle , like the Winchester 95 was some years back.
Modern metalurgy would insure no problems of bolt cracking so long as pressures were kept reasonable.
An added safety lug would be all it would need to satisfy gun company lawyers.
A scaled back version in the .30-30 class cartridges, or those rimmed cartridges of similar back ground should would be a great woods rifle.

A strenghtened Krag should also be suited to the .303 for that matter.

The Krag and the Mosin Nagant have the best feed mechanisms for rimmed cartridges, superior to the Lee Enfields in that respect.

Char-Gar
01-07-2010, 02:56 PM
The Krag action is strong enough as long as pressures are kept to the original 40K limit. Cracked bolt lugs are not the result of any inherant weakness with the design or metal, but to folks pushing the pressure past the design limits. At least that is what Hatcher says in his notebook.

leadman
01-08-2010, 01:52 AM
Just a little off-topic, but the CMP is selling new Criterion 30-40 Krag barrels. At $199.95 not cheap, but would probably save quite a bit of money over having a 'smith do the machining.

I have a Krag Sporter that I think has a Springfield barrel on it.

I've got as bunch of old magazine that had Springfield barrels for a couple bucks.

madsenshooter
01-14-2010, 12:59 PM
The CMP's barrels have been showing up with oversize bores so far. Just like the originals, like about 6 of mine, that slug .301/.310. Not a problem as long as one is aware of it, but it seems not many are aware, especially j-word shooters who go on banging away with .308 bullets. Lapping the lug moves the face of the bolt away from the breech face and that headspace has to be recovered somehow, either by putting the barrel further in, or making your brass from something with a thicker rim, like the .405 Win. I have a few that bear, but headspace wasn't increased by doing it, somehow, by someone.

pojv
01-14-2010, 06:46 PM
I have a quick question on Krag actions, as I have 3 Krags. One of the Krags has a side scope mount that with a scope on it the safety is not useable, has anyone found a work around for this?
The main reason I am asking is I am converting one of them to 25 Krag AI and will have the same style scope mount.

Thank you
Phil

Kragshooter
01-14-2010, 08:52 PM
I bought my Krag from a great ole guy that passed or I would ask him what safety he installed. It works fine with my scope set up. The mount is a Williams and it is offset but works just great. Not a great pic but here it is.

http://i439.photobucket.com/albums/qq113/ftlupton/3-40Krag.jpg

pojv
01-14-2010, 11:13 PM
Thank you very much for the picture; I will see what we can do.
Phil