World War 8mm Mauser: Surplus ammo accuracy/reliability/velocity test

[Phosphorus32]

I'm bummed about the Persian stuff.  I was hoping that by using up all the crown headstamped rounds (about 50 of them out of 500) I had 'solved' the hangfire problems.  I guess not.  Maybe I'll put it up for sale: Terrifyingly accurate ammo!   

Old Iranian surplus ammo, a parting gift from The Shah and SAVAK to hang us up on the firing line 

[Blicero]

Very nice Kev...   threads like this are awesome to read and very informative!

Thanks buddy. Between good Samaritans contributing ammo in the name of science and our man Phosphorus graphing pie charts and calculating standard deviations, I never thought this experiment would be so popular. For me it was just an excuse to learn a little something about the caliber, and to mix up my range routine.

Except for German ammo, I think we've learned something about all the nations' 8mm that's available to us on the market. Now I would like to spend some more time looking strictly at what each nation can do in the accuracy department. Unfortunately I am out of Yugo m75 and I'm down to only 30 rounds of '50s Yugo. I'd like to study what the Greek is capable of, I'm in the process of sweet-talking RM out of his stash.

[Phosphorus32]

I fell down on my job as geek 

The K98b vs. the shorter K98k barrel resulted in 5.7%,  3.7% and 3.6% higher velocities for the Ecuadorian, Greek and Turkish ammo, respectively.

Here are the average velocity and standard deviation statistics for the ammo on the second range day




Recapitulating the previous data for the sake of comparisons

[running-man]

Ha!  Look at that quality Iranian ammo!  10 round Std. dev better than equal rounds of Turkish, Equadorian, Yugo, or Eqyptian! 
Yup, terrifyingly accurate!  Who wants to buy it off me?!  I'll sell for the right price!!! 

I'll have to take 60 rounds or so out to the range and see how it does with a bigger sample size than the 20 I shot last time.  I swear I had 0 issues with the non-crown headstamp stuff out of the 24/47.  I think your K98k is just a junker Kevin.  Maybe you should get rid of that POS?  I'll take one for the team and toss you $100 and 200 rounds of Iranian ammo for it!    

[Blicero]

I have a few true junker k98s. Be careful what ya offer 

I just landed 300 rounds of Turk thanks to a local facebook deal...from one of the groups that didn't expel me for being a round 'em up gasser of undesirables. Once I pick up a few more packs of m75, I'm going to look strictly at accuracy. I'm worried that between human error and inconsistent loads, an accuracy test might not be too honest or revealing.

Phos, I appreciate you sorting this data out. But can you put the data into practical, real world terms? What would those numbers translate to if you're a hunter, sharpshooter, soldier, or casual plinker?

One thing I failed to mention, the Iranian ammo cases were a bit out of spec too I think. All of the rounds required a bit of force to get the bolt fully closed. I don't know if that's improper bullet seating or OAL problems or improperly formed brass, but closing the bolt on them felt stiff & tough.

[Phosphorus32]

Phos, I appreciate you sorting this data out. But can you put the data into practical, real world terms? What would those numbers translate to if you're a hunter, sharpshooter, soldier, or casual plinker?

Good question. Of course velocity is just one of many important parameters. The ammunition that exhibited small standard deviations should shoot very consistently (excluding those hang fire lots  ), assuming the bullet weights (and shape) are virtually identical as well.  That's an important assumption. If it's incorrect, tight velocities are worthless. But it's really, really unlikely that you could have sloppy bullet weights and sloppy powder loads matching up to get tight velocities. As a relevant aside, I weighed about 20 Sierra Matchkings and their weights were identical, within the limit of precision of my electronic scale. That's what everyone wants. The other aspect of bullet weight that we just touched on earlier in this thread is the mix of heavy and light ball ammo in your round up and how that factors into ballistic energy, E = 0.5mv², where m = bullet mass and v = velocity. 

Consistency is good for all the classes of shooters you mention, but potentially life and death for a sharpshooter/sniper, whose objective is consistent, predictable shot placement to achieve 1 shot = 1 kill results. Of course, none of these are hunting cartridges, but I don't think you were referring to that, the hunter needs good accuracy and high energy for stopping power, and bullet expansion to inflict lethal damage.

[Blicero]

Thanks to our man Phosphorus, I was able to experiment with some Israeli surplus 8mm. According to him this ammo uses 178 grain projectiles (correct me if I'm wrong there, I don't have the box in front of me), which struck me as odd since I thought military ammo came only in 150 & 200 gr. And it is boxer primed, bonus. I'll send you back the brass, Jon.

As an aside, my shooting buddy was checking out the Israeli ammo & he asked if this was another freebie batch. I said yep, my friends found this project interesting enough to contribute to the cause. Then I reiterated the "I love data" statement Phos had previously said and that set my buddy into a heavy chuckle. He took some guesses at the type of personality that would utter such a phrase...let's just leave it at he knows RM & Phos pretty darn well

At any rate, the Israeli ammo is a pleasure to shoot. It all fired on command and cycled smoothly in the Lubecker. We were a little vexed by the velocity, we had guessed 178 grain 8mm would be in the 2600+ fps neck of the woods. It shoots about 7" over POA. It was passably accurate- I shot two groups of 10 shots each, one measuring 5.75" and the other 8". Without referencing my previous results, I'm tempted to say this ammo had an equal or smaller velocity spread than any of the other nations. I doubt there's much of this ammo floating around, but if you can find it for under $.45/rd. I'd say you need to jump on it. Great stuff.

2471 fps
2516
2501
2499
2522
2519
2504
2533
2548
2552
2556
2555
2538
2503
2531
2548
2502
2550
2524
2552

[Phosphorus32]

Data! 

Yes, they were 178 grain, as measured on my digital balance (just one example).  They are FMJ (copper clad, presumably with a lead core, since they are non-magnetic), have a cannelure and no boat tail.  The first data point looks like an outlier in a scatter plot, perhaps the first shot out of a cold barrel?  I didn't run any statistical analyses to formally exclude it but the numbers in parentheses are without that first datum.  Average was 2526 (2529) fps and the standard deviation was 24.1 (20..  Similar to many of the other types of ammo, other than the M75 which was much tighter, and the Iranian which had a very broad distribution.

Glad your friend was amused. I'd analyze his bemusement but I don't have any first hand data on which to conduct an unbiased investigation