A Model 1891 to keep my 1898 Krag, 1891 Mosin-Nagant and 1896 Swede company.

[RBruce]

Love those old long guns.

[vintage hunter]

Nice find. Looks to be in above average condition for 116 years old. The early ones are hard to find in any condition, at least around here anyway.

[RBruce]

Just think, back in the early 1900s these four were on the same side!

[Aragorn243]

I've been watching for one of them for several years now with no luck. I wanted an Italian rifle and this one was the only one that didn't feel "toy" like to me. I handled one at a gun shop a few years ago and came close to buying it as the price was right but it was very badly corroded all along the barrel channel and I feared what I would find when I took it out of the stock.

[RBruce]

Is there a way to determine the actual diameter of the bore without having Cerrosafe or similar product?

[Patrick Chadwick]

Oil the clean bore liberally, and then whack a soft-lead .31 ball down it, like this:

Drop the ball in at the chamber and repeatedly drop a yard length of 1/4" brass rod onto it, giving the rod a downwards flick with your fingers to accelerate it. A brass rod cannot hurt the rifling, but provides a huge impulse to drive the ball down.

If the ball stays tight all the way the rifle is a prospect. Measure the ball and start thinking about possible bullets.

If the ball falls through the last couple of inches, the muzzle end is hopelessly worn and you can forget it.

:wave:
Patrick

[RBruce]

Patrick, Since I don't have a .31" soft lead ball, I drove a .280 cast lead bullet into the muzzle. The measurements where the lead was displaced are .671mm and .696mm, lands and grooves. Can you determine the bore from these readings? If so, would standard 6.5mm bullets be likely to work in this rifle?

[Patrick Chadwick]

Since I don't have a .31" soft lead ball, I drove a .280 cast lead bullet into the muzzle.


That's fine, as long as you managed to get it right through the barrel! If you only drove it into the muzzle and out again, then you may be measuring a worn muzzle end, and do not know if the rest of the barrel is the same or tighter.The trouble with measuring the bore is that with a 3-groove bore you do not get a clean "Over grooves" figure, as there is a land opposite each groove. I hope your rifle has a 4-groove bore, in which case the max/min diameters on the slug do indeed correspond to the groove/land diameters.

Now for the worrying bit: The CIP bore/groove dimensions are given as 6.50 / 6.80 mm for a 4-groove barrel. You have measured 6.71 and 6.96. That sounds like a badly worn barrel. So please check your measuring devices (zero on micrometer or slide gauge, for instance).
As I wrote in my previous post, if the barrel is seriously bell-mouthed, there is not much you can do about it, and the rifle will probably shoot very poorly indeed.

If, on the other hand, the barrel is worn all the way down, i.e. oversized but constant, then the situation is not hopeless, but very awkward. You will need bullets that are thicker than the standard 0.264" (6.70 mm). If your measurements are correct, then a 6.5mm bullet will slide right into the muzzle. So try exactly that. If the 6.5 /.264 does indeed slide right in and stick somewhere down the bore, then the situation is hopeless. If it slides right through, then you have 2 options for shooting a) use the Hornady .268 (6.8mm) bullet made specifically for the Carcano - if you can still find them or b) use hard cast lead bullets with a diemeter of 6.9mm. The trouble with the first option is that there will be a lot of gas blow-by, and the trouble with the second option is that the neck of a loaded cartridge may be so enlarged that the cartridge will not chamber.

Check those measurements, and get hold of a piece of lead that you can drive right through the bore!

:wave:
Patrick

[Patrick Chadwick]

Here in Mauserland one can get cast lead bullets in 0.270" and 0.272". Measure the neck diameter of a fired case. Measure the wall thickness.

Neck diameter - 2x wall thickness = inside neck diameter.

Why not measure the inside neck diameter directly? By all means do so, but the result is likely to be a trifle different. Smaller if you do not have the caliper jaws positioned perfectly on axis. Smaller because of the thickness of the jaws. But larger if you try to measure too tightly and force the case out of round. I find the first method more reliable.
Anyway:

Inside neck diameter - 2 thou (unless you have a bench-rest setup) - bullet tolerance (you will have to size all bullets for this kind of fine tuning) = the absolute maximum bullet diameter that you should try to chamber.

If the resulting bullet diameter is still too small for a good fit it the bore, then the absolute last chance is to use moderately hard bullets, and hope that they slug up enough to fit. But the softer the bullet the more rapidly you will get bore leading. There is no easy answer.

:wave:
Patrick

[RBruce]

Looks like it is a worn barrel. I drove a .280 piece if soft lead into the chamber end and got 6.61 mm and 6.83 mm. The 6.5 bullets I have are 6.66, 6.67 and 6.8 in diameter.

[Patrick Chadwick]

Well I have brought back several guns from wallhanger status to usable, but that sounds pretty bad. Land diameter enlargement towards the muzzle means gas blow-by, but the bullet is still being held on course by the grooves, so the rifle may still shoot straight. With black powder rifles one can pack in a lot of lube, so that the hydraulic seal is (hopefully) maintained right up to the muzzle. However, that is not a solution that I have heard of being applied to smokeless rifles.

Groove diameter enlargement as well means the bullet is now longer axially guided as it approaches the muzzle. So it will develop a yaw before it emerges, and that will probably cause tumbling. I would not spend too much time on it.

:wave:
Patrick

[RBruce]

Thaks Patrick for providing guidance. Would you recommend sticking with the Hornady 160 gr bullets that are slightly oversized?

[RBruce]

I fprgot to mention that my rifle built in 1896 has four grooves. also, what would be the recommended beginning load for the Hornady 160gr Carcano bullet? --TIA

[Patrick Chadwick]

Yes, I would try the 312 Hornadys in the Mosin, before giving up on it. As for loads, the 0.268 Hornady Carcano bullet has been the subject of intensive, verging on heated, discussion. This is a bullet that is definitely oversized for an as-new, in-spec Carcano, so whether or not you can use it depends on how badly the bore is worn. In this situation, there are serious safety aspects to be considered, and if you search the forum there is a link somewhere to a handwritten table that is supposed to have originated at Hornady. There seems to be a conspicuous lack of printed info from Hornady itself, so there is no recommended starting load. Using bullets that would be oversize for an in-spec rifle is something that you undertake entirely at your own risk.

You must drive a slug all the way down the bore before considering such components. Measuring at the ends alone is not adequate. If, for instance, the bore is worn at both ends (quite possible) then using a bullet based on that info might result in an oversized bullet plugging the bore some way down. Not a good idea. Accurate measurement is a precondition, not an option.

:wave:
Patrick

[shop tom]

I agree with Patrick. An accurate slugging of any milsurp is highly advised, especially on one in which the bore size is known to vary in spec.

Here is a good read on Carcano reloading in general:

SHOOTING THE 6 (http://personal.stevens.edu/~gliberat/carcano/emary.html)

tom

[jmoore]

There seems to be a conspicuous lack of printed info from Hornady itself, so there is no recommended starting load.

Hornady does have a load data table for the 0.267"+ bullet in at least one recent edition. (The 7th ed., I'm pretty sure. The cover of the 8th edition is not one that I have at home, so it appears I'm behind at little.) Haven't seen anything for the 7,35 cartridge, though. As usual, I won't post any load recommendations. Just get the book and follow the instructions.

[tokguy]

See now I have to close the deal on a Carcano.:rolleyes:
I also have a 30 - 40 Krag(Bubba'd but S.N. is 1994, that's kinda cool), a Finn M-39 & a 6.5 X 55 Swede.
OP , you must be like me...I appreciate the different mechanisms of Milsurp bolt actions.
I've also a mildly Bubba'd Ross and K98.
Carcano and maybe a 1895 Steyr are next on my wish list.

[RBruce]

Using Nosler partition 140 gr bullets - .264 diameter. 34702

[Aragorn243]

Doesn't look like the bore's shot out to me.

[RBruce]

Well, my jackleg method of slugging the bore at the muzzle lead to faulty data. But, I had near catastrophic results using the Hornady 160 gr .2675 bullets. The Hornady 160 gr .264 bullets worked fine, but not as accurate as the 140s.