Mauser shooting low

[Mosin-Marauder]

My M24/47 is shooting about 4 inches low, with 196 grain Soft points and a bit lower with 200 grain FMJ BT Match ammo, both from PPU. Any way to raise my POI a bit?

Thanks!

Regards,

-Mo.

[Slamfire]

Most military Mausers shoot high!.

I would like to ask the obvious question, what about raising the rear sight?

Assuming there is something that prevents you from doing this, let me recommend a sequence of actions.

I glassbedded my Yugo Mausers, the bedding was so bad that they shot chaotically. This is not difficult to do, route some wood, pour in Brownells Acuraglass gel, make sure you have coated the metal with Johnson paste wax or your favorite release agent. Wait till its cured and knock the action out and clean up any glue spill overs.

Having the action firmly bedded, instead of bowed, as 99% of these actions are after 70 years and a couple of rebuilds, will provide round groups and more predictable point of impact changes with bullet weight changes.

Now you can simply shorten the front sight, with a file, or buy a short front sight, and that will fix your elevation problem with one particular bullet weight.

I am going to assume that the M48 has about a 22 inch sight radius. Removing 0.0122" inches of material from the sight will raise the POI 2 MOA.

[Mosin-Marauder]

I will raise the rear sight and see where it hits, it may seem a bit stupid that I haven't already done this but I was just worried the elevation wouldn't be on target at other ranges if I raised it to 300 Meters. Thanks!

[TX Hunter]

Your lucky, most of the Yugo Mausers shoot High. Just raise Your rear sight a little until You get close. If You need to file the front sight down a little.

[kraigwy]

If your mauser is shooting low and you cant raise the rear sigh you need to lower the front sight.

How much depends on how low its shooting.

This is fore 100 yards. 100 yards is 3600 inches (36 X 100 = 3600)

Measure your sight radius (front sight the rear sight) I don't know what it is on your rifle, Lets say its 24 inches.

Divide 24 (sight radius) by 3600 (number of inches in 100 yards.

24/3600=0.00667

If you lower your front sight (file down) 0.0067 it will lower the impact 1 MOA

Yours is shooting 4 inches low. 0.00667 X 4 = .02667.

So mill or file your front sight down 0.02667 and you should be zeroed at 100 yards.

Again I used 24 inches for the sight radius. Measure yours and use it instead of 24.

R = Your Sight Radius

R/3600=X X*4 gives you the measurement you need to lower your front sight.

[TX Hunter]

Are You saying Roughly six and one half, thousands of an inch, per one inch of elevation at 100 yards ?

[grey.ghost]

Very good info kraigwy. Thank you

[g.willikers]

I was just worried the elevation wouldn't be on target at other ranges if I raised it to 300 Meters.

That's why you have adjustable sights and keep the info in a shooter's log book.
You do have a log book?

[hooligan1]

Hey Mo, humor me and take bolt out and glance down the bore, could be bent. I purchased a yugo about two weeks ago that is all numbers matching and its basically flawless, however barrel is bent downward in the last 10" of barrel toward front sight.. Rifle doesnt appear to be beat up or otherwise abused. Haven't fired it yet, but I'm sure it will shoot low also....might send it to get straightened because of the condition its in...really nice piece with shiny perfect bore other than bent, and its only slight but I can see it.

[Mosin-Marauder]

I honestly can't tell if it's bent. It looks pretty normal to me.

[kraigwy]

Mr Kraigway

--------------------------------------------------------------------------------

Are You saying Roughly six and one half, thousands of an inch, per one inch of elevation at 100 yards ?

More like 6 2/3 thousands, but again, I just pulled that number (24 in. sight radius) out of the air.

I don't know the actual sight radius. The numbers will be different.

[TX Hunter]

Kraigway thanks for the explanation. I am about to have file down a tall sight I put on My Mauser.

[wpsdlrg]

4" low at what distance ? I assume that you mean 100 yards. If so, 4" is well within the "acceptable" envelope for these rifles, as per Yugoslav army specifications. So, these rifles tend to shoot high at anything less than the zero distance.

The 24/47, as with the M48 series rifles, has a standard battle zero of 300 metres, with the specified military ammo (of course). Your ammo, needless to say, though the bullet weights are very close, obviously differs enough from the military standard to cause the difference in POI. The standard military load was a 198 grain FMJ at 2300 atm (about 34,000 psi), producing about 2360 fps.

4" of deviation at 100 yards, let alone at 300 metres, will probably not be possible to resolve with the standard adjustable rear sight. The adjustment notches are far coarser than that. So, I have a strong feeling that you will need to file your front sight to get the change you need.

[bumnote]

I bet someone put a taller front sight blade on it at some point. Some blades are marked +1, +2 etc. All my Swedes have the blade changed out so I can zero it under 300m.
My FN Model 1950 has its original blade on it and the rear sight needs to be a notch or two to be zero'd at 100yrds...but that's with my eyes. Other shooters who've shot it don't have to do that with it.

[ttarp]

I'm a little late to the party here, but I thought it worth mentioning.

I haven't shot any of their match ammo, but the plain 196 soft points from PPU are loaded pretty light, the soft recoil is noticeable. They shoot maybe an inch low give or take out of my K98.

When I switch to S&B ammo, it kicks like a horse and shoots 4-5 inches high. So its a possibility if you try some hotter ammo it'll take care of the problem. Good luck at any rate.

[emcon5]

Good point. When the 8X57 was introduced, it had a 0.318 bore, and was later changed to .323, and because of this, most of the ammo you can get in the US is crap.

US manufacturers were afraid some dimwit would try and shoot a full power .323 through their .318 bore Gewehr 88 and blow up the gun, and hurt themselves. Europeans figured if you don't know what ammo your gun can safely shoot, you are a moron and deserve whatever happens to you.

Regardless, there are two specifications for what we call 8mm Mauser, the US SAMMI spec "8MM Mauser", which has a max pressure of 35K psi, and the CIP "8x57 IS" which has a max pressure of ~56K psi. To further muddy the waters, "8x57 IS" is often written as "8x57 JS, evidently because the Germans used a Gothic script, and the I looked like a J.

Generally, what you can get in the US is "8MM Mauser", and it the anemic SAMMI spec.

Privi Partisan actually makes both, if you look at their online catalog, they have entries for both "8MM Mauser" and "8x57 IS", with the latter having a higher velocity for the same bullet. For example, the "8x57" IS 198 gr FMJ is 2425 FPS, (essentially the 1934+ military load), but the "8MM Mauser" 198 gr FMJ is only 2180 FPS. Naturally, they only sell the wimpy stuff in the US.

Wolf Gold is made by Privi and loaded to 8x57 IS specs, 196 gr SP @ 2461 fps, but I haven't seen it around in a while.

Remington's and Winchester's only offerings is 170 gr @ 2360fps. Federal's only option is even wimpier 170gr @ 2250 FPS.

Hornady and Nosler seem to be the only US folks making "real" 8x57 ammo, Hornady has two options, a 195 hunting bullet and a 196 gr match, both @ 2500 FPS, which is pretty close to the original military load.

Nosler has a 200gr AccuBond or Partition at 2475 fps, and a 180gr Ballistic tip at 2600 FPS, but they are really proud of them, at about $2.50 per round.

Seller & Belot and Norma both make a few 196 loads at ~2600 FPS, but availability is spotty, and while the price on the S&B is decent, the Norma stuff is up in the $2.50/round neighborhood.

If all you plan on shooting is the low power Privi stuff, then modifying your front sight is not a bad idea, but keep in mind that the range settings will not match the ballistics of the ammo because of the lower velocity. You are probably better off just using the rear sight slider, going up to 200 and see where it hits.

[Slamfire]

US manufacturers were afraid some dimwit would try and shoot a full power .323 through their .318 bore Gewehr 88 and blow up the gun, and hurt themselves. Europeans figured if you don't know what ammo your gun can safely shoot, you are a moron and deserve whatever happens to you

It turns out the Germans were also very worried about 323 bullets down the bore of their M88 rifles. They were having barrel blowups in 318 barrels with period ammunition, even after increasing the free bore. The primary cause was poor barrel steel. No one intended to make poor quality barrel steel, it was just the technology of the period was so primitive that the steels of the day were very inconstant and low quality.


I don't think SAAMI standards are unrealistic for period actions. While I have not found an explicit statement to the design loads that Paul Mauser used, you can infer what the actions were designed to hold. There is information about the proof pressures used in M98 actions.

Rifle Magazine Issue 159 May 1995 Dear Editor pg 10
http://www.riflemagazine.com/magazin...159partial.pdf

Ludwig Olsen :

Mauser 98 actions produced by Mauser and DWM were proofed with two loads that produced approximately 1000 atmosphere greater pressure than normal factory rounds. That procedure was in accordance with the 1891 German proof law. Proof pressure for the Mauser 98 in 7 X57 was 4,050 atmospheres (57, 591 psi). Pressure of the normal 7 X 57 factory load with 11.2 gram bullet was given in Mauser’s 1908 patent boot as 3,050 atmosphere, or 43, 371 pounds.

While many Mausers in the 1908 Brazilian category will likely endure pressures considerably in excess of the 4,050 atmospheres proof loads, there might be some setback of the receiver locking shoulder with such high pressures

Kunhausen shows similar numbers in his book : “The Mauser Bolt Actions, A Shop Manual”

Rifle & Carbine 98: M98 Firearms of the German Army from 1898 to 1918 Dieter

Page 103. M98 Mauser service rifles underwent a 2 round proof at 4,000 atm gas pressure, 1 atm = 14.6 psi, 4000 atm = 58, 784 psia.

The lugs broke on 1:1000 rifles used by the Bavarian Army Corp!

Gun Digest 1975 has an excellent article, “A History of Proof Marks, Gun Proof in German” by Lee Kennett. “The problem of smokeless proof was posed in a dramatic way by the Model 1888 and it commercial derivates. In this particular case a solution was sought in the decree of 23 July 1893. This provided that such rifles be proved with a government smokeless powder known as the “4,000 atmosphere powder”, proof pressure was 4,000 metric atmospheres or 58,000 psia.

The 4000 atmosphere proof was standardized for the 1893 and continued after 1911.
The article indicates it was applied to the 1898. The 1939 German proof law called for proof at 130% of service load pressure. The maximum working pressure of the German 7.9 sS cartridge was 47kpsi (per forum posters), so presumably the proof pressure for a late Model 1898 would exceed that by the normal 30%, or 61k psi.


Unless someone can produce credible data as to the proof standards of later 98 actions, and the design limits used by Paul Mauser, I am going to state that it is reasonable that the action was designed to support cartridges of 43, 371 psia with a case head diameter of 0.470”. I believe that a pressure standard for these rifles of 43, 371 lbs/ in ² is reasonable based on the SAAMI spec pressure of 35, 000 lbs/ in ². Obviously SAAMI researched this issue, probably determined original pressure standards, then used wise judgment about the age, uncertain previous history, unknown storage, usage, the known limited strength of period plain carbon steel actions, and as an industry, they were are not willing to accept the liability involved with selling new ammunition of a higher pressure.

Later actions, and I consider the actions made in the 1930's to generally fall in that category, the steel was better so pressures could be bumped up a bit, but it is folly to chamber a military Mauser action in a high pressure cartridge or worse, as a belted magnum.

[emcon5]

CIP specs show the max pressure as 3900 Bar, or ~56.5K PSI.

http://www.cip-bobp.org/homologation...-en-page57.pdf

SAMMI spec is 35K PSI.
http://www.saami.org/specifications_...essure_CfR.pdf

For comparison, the .30-06 is ~60K PSI.
The 7mm Mauser, from SAMMI is 51K (CIP max pressure is the same as 8X57, ~56.5K).

The 8mm Mauser SAMMI ammo is woefully under powered crap.

[TX Hunter]

I am having similar problems. Mine shoots pitiful low with Factory ammo, and rediculas high with hand loads.

[wpsdlrg]

Unless you are willing to change the sights, you are left with trying different handloads, including different bullet weights and charges/ powders, in order to get your rifle zeroed. Remember, these were designed as battle rifles, not target rifles....and were designed during an era when the standard military thinking went more toward massed volley fire at significant range, rather than individual marksmanship. Hence the 300 metre standard zero distance.

My M48 was always a "beater" ("parts rifle", to be exact). So, it has gone through a number of changes, including re-barreling, shortening the barrel to 17", re-working the stock to a "sporter" configuration, glass-bedding the action and barrel....and different sights. I get 4" groups at 100 yards, with iron sights of my own design (hunting sights really). I handload all of my ammo, including paper-patching cast bullets for this rifle. I did have a 4X scope on the rifle for awhile, with which I could get 1.5" groups at 100 yards. I prefer irons, though and the challenge of shooting them.

So, the old Mausers can be made to shoot well. Depending on the individual rifle and the loads used, it just may require some "tweaking". Part of the fun, to me, anyway.

[hooligan1]

I took my 24 to the range Wednesday, and found it to shoot 3" low at 25 yds. I shot it at that distance to see if it had any desirable consistancy.
It did make a nice 6 round hole, and seemed to like the 196 grn fmj ammo I had for it.

My next test will be to raise rear sights enough to hit close to bullseye at every target to 100 yds so I can enjoy my rifle..I do not wish to file my front sight, and I haven't ruled out sending it to have barrel straightened.