Brazilian Mauser crazy groupings

200250126

200250126

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I inherited a Mod 1908 Brazilian Mauser 7mm of unknown provenance. It has military iron sights, (sliding rear tangent and front blade) and figured as it's not in great shape and has no scope it would be a handy bush push rifle for under 100 yards and I wouldn't care if it gets scratched or banged up in the bush. It can not consistently group for the life of it. To cover off variables all my testing was done on a bench with front and rear sand bags. I was shooting factory loads at 140 and 145 grain as commercially available 7x57 is getting scarce not to mention expensive. I read somewhere that the military issue FMJ may have been about 180g but I can only work with what I got.

This thing will shoot a 10 inch group at 25m. Yes, 25m off a bench. It'll shoot a 20 inch group at 50m. I didn't even bother at 100m and waste my money. There is no rhyme or reason to the grouping either, it'll shoot low 4 inches, then off to one side a foot then the other side 9 inches off centre.

Looking through the bore I can see the rifling, it's not worn down smoot but then again I can't tell anything more than that. The action and the barrel fit snug in the stock and the sights are tight.

It's pretty much unusable in it's current state. I didn't pay for the gun as I inherited it, but I'm wondering what options I have at this point. It's not worth anything to anyone in the manner in which it shoots, also the stock has been bubba'd so it doesn't have collector value. Maybe the action is worth something to someone? Could I have it re-barrelled? Only if it's not prohibitively expensive to have a new 7x57 barrel made and the likeliness of same on a gun that isn't worth anything.

I'm open to suggestions in regards to either its inaccuracy or having the problem remedied.
 
Interesting. I can't help but think the rifling isn't the issue, smooth bore muskets from the 1800s do far better than 10" at 25yds. I wouldn't think the difference in bullet weight could cause that much variation either, and by that I mean I doubt heavier bullets will all the sudden make this rifle a shooter.

When you look from the muzzle end, what does the Crown and the last few inches of rifling look like? My first guess would be something is loose, maybe the rifle really needs a bedding job or the action screws are bottoming out before actually being tight?
 
Good lord, mate, that's tragic. Is the crown egregiously buggered maybe?

if a guy could find a good barrel for it, it'd be worth doing. Maybe do something fun with her. Bubba's already done his terrible work, the rotter, so she's something of a blank canvas.
 
Oh, I forgot to ask does this rifle have any sentimental value? That would help determine whether it's worth the cost to try and fix... That said, a cut and crown is pretty cheap, although you'd have to get a front sight put back on...
 
The Brazilian 1908 Mauser chambered for the 7x57 has a slower twist rate than most other rifles chambered for that cartridge.

The Brazilians used a load with 140 grain bullets, which generated 2850 fps out of a 29 inch barrel.

This load can easily be duplicated using CCI 250 magnum primers/ 51.0 grns of W760/139 gr bullets.

This load is over max for Mod 95 Mausers but the Brazilian M1908 is a large ring Mauser, made with the best steel available at the time of manufacture for the purpose. The Brazilians loaded to pressures that were safe under Equatorial conditions. I would suggest you start reloading for that rifle or find someone that can do it for you. Save the brass, it's expensive.

As for your rifle not shooting well, that's hard to pin down on your limited description.

Usually if the bores are decent Brazilian Mausers will shoot better than the people shooting them are capable of.

I would suggest a strip down to make sure the bedding is OK, as in no cracks or soft from oil, or filled with dirt. Another thing that is necessary for these rifles to be consistently accurate is that the rear bedding pillar is still in place. Make sure the recoil shoulder is still tight as well. If any of these are missing or sloppy, likely it's the cause of your accuracy issues.

I have two M1908 rifles in my safe. Both consistently shoot into 1/2 moa if I do my part.

I had one that didn't shoot well about ten years ago. It had a warped fore end, which put pressure on the barrel.

I have a neighbor with the same rifle as you have, in similar condition. The bore is about 80% on his rifle and he shoots it with open sights. It's a very accurate rifle.

He refuses to use handloads. Just doesn't trust them, so like you he purchases his ammo from the local gunshop, which has it in stock, from several manufacturers. He also complains of cost, but it really isn't more expensive than other commercially loaded ammo. It seldom goes on sale though.

That action is strong. Tradex has some Zastava take off barrels that will fit your action for very reasonable prices.

I really like the 1908 actions, they are much smoother and better finished than the later M1935 actions. Both are excellent.

Your rifle is suitable for any standard length cartridge.
 
Usually the 1908's are in very nice shape, are you sure it isn't one of the later conversions to 30-06 as some/most are not in nice shape?
 
MiG25 said:
Usually the 1908's are in very nice shape, are you sure it isn't one of the later conversions to 30-06 as some/most are not in nice shape?
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That would explain the accuracy!

Would a 3006 chamber be able to reliably set off 7mm mauser though? Or would the 7mm just fall into the throat? Wouldn't that blow out the shoulder some so the fired brass would clearly look different from an unfired round?
 
I'll try to post a picture. I was considering something majorly wrong with the crown of the muzzle causing rounds to veer off wildly. I'm assuming it is a 7x57 as way back in the registry days that's what it was verified as but I am familiar with those 3006 conversions. I've had zero problems with feeding and ejecting and there's been no problems with the spent casings looking deformed.

I had one group at 25m that was 4 rounds in an inch or so group, (way off centre but all together) and one round 9 inches away, again no rhyme or reason. And again, it doesn't group the same from shot to shot. These rounds are spread out in random fashion most times.

The barrel is quite short but looks original. Maybe 22 inches or so off the top of my head. It does not feature a full length wood stock but is more of a sporter style. Again I will try to find photos or a photo of something similar.
 
call2arms said:
I am No expert on Brazilian Mausers but are we sure it is 7mm?
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That was my first thought. We’re talking 40 moa here. That’s not subtle.

MiG25 said:
Usually the 1908's are in very nice shape, are you sure it isn't one of the later conversions to 30-06 as some/most are not in nice shape?
Click to expand...

Hmm.

30-06 on the left, 7mm on the right.

84723717-0424-491-C-B394-6-DC5-E5-C93-D16.jpg
 
If the bullets are not hitting sideways and the brass badly deformed, then the caliber is correct.
Random flyers suggests something is loose. Also it might be worth spending some time cleaning the bore. It is possible that there might be a significant build up of metallic fouling. We have seen this with some older rifles and in particular where the military bullets were nickel plated.
 
Maybe it is a 1909 in 7.65x54, i suspect a 7x57 would chamber and look normal after firing.

Maybe someone spun an 8x57 barrel on it.
 
Just throwing ideas out there.

Does the barrel SN match the reciever SN.

What are the words on the action?

Wouldn't be the first time someone mixed up the 1908 and 1909, let along the Canadian Gun Registry, it was loaded with Lee Enfields registered as "Tonsper" and "Tonsperu", confusing the proof marks with the manufacturer.

https://www.icollector.com/Sporteri...-65mm-cal-22-barrel-black-finish-wo_i18254615
 
Given the gun was sporterized at one point, someone thought it had a decent barrel. I would look at the bedding of the action in the stock. In many cases, when guns were sporterized, little attention was paid to a proper fit. The action screws may appear tight, but the action is loose because of interference with the magazine box. Alternatively, the barrel my be binding excessively in the stock.
 
cosmic said:
Given the gun was sporterized at one point, someone thought it had a decent barrel. I would look at the bedding of the action in the stock. In many cases, when guns were sporterized, little attention was paid to a proper fit. The action screws may appear tight, but the action is loose because of interference with the magazine box. Alternatively, the barrel my be binding excessively in the stock.
Click to expand...

But I can’t imagine something like that giving 10 inch groups at 25 yards though... it’s gotta be something more profound.
 
Also maybe sporterized isn't the right term. It is definately a milsurp stock not a sporter/hunting style stock but its not the long forend with a bayonet lug like most mausers. But I am having trouble even googling something similar.
 
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