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Transplanted from old YW site:
gschwertley
saddle soap
Posts: 1525
(12/18/05 6:16 pm)
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Still more experiments with the 8x50R
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Another trip to the range today found me still looking for answers with the 8x50R. On this occasion, I tried some of the 250 grain round nose Hornady bullets resized to .330 that I referred to in my previous post entitled "Have I found a good bullet for the 8x50R?" Indeed I have. The rifle likes these bullets.
My experiments involved some of these 250 gr. bullets resized to .323 and .330. The results are as follows:
250 gr. Hornady jacketed RN bullet .338 resized down to .323
50.0 gr. Hodgdon H-1000
CCI #250 magnum primer
Buffalo Arms brass (re-worked .45-70 RP brass)
Average muzzle velocity: 1708
Standard deviation: 18.69
Same components as above, but with bullet resized to .330:
Muzzle velocity: 1824
You will note the difference of over 100 fps. due strictly to the bullet diameter. As I have said before, with the non-obturating base .323 bullets in this caliber, some velocity is lost from gas by-passing the bullet through the grooves.
Same components as above, but using 46.0 gr. IMR 4350:
Average muzzle velocity: 1675
Standard deviation: 14.38
Good accuracy was obtained with all of the above loads.
Using the heavy 250 gr. bullet, the rear sight required elevation only to the first notch at 50 yards (lowest, fixed setting in the bottom of the sight ladder) to compensate for bullet drop.
You can expect decreased muzzle velocities using heavy bullets and slow stick powders. However, both work best with each other and give low, safe pressures and reasonable recoil. With a powder as slow as H-1000, for example, you can't get enough powder in the case and still seat the bullet to get even close to a dangerous pressure.
Other experiments with this caliber on the same day:
170 grain RP jacketed RN bullet .323
49.0 gr. H414
CCI 250 mag primer
Reworked military 8x56 cases
Average muzzle velocity: 1788
Standard deviation: 87.51
Lousy spreads and not particularly accurate.
200 gr. Nosler partition bullet .323
47.0 gr. H414
CCI 250 mag primer
Reworked Graf 7.62x54R cases
Avg. muz. velocity: 1629
Standard deviation: 13.89
Not accurate.
Both of the loads above with H414 powder manifested some semi-burned powder residue remaining in the chamber upon case extraction. This would cause subsequent rounds chambered to suffer tiny compression dents after being fired due to impressions made by the powder granules. Bad accuracy, bad spreads on the one load, and unburned powder tell the tale told before. That is, some ball powders don't work well in large, bell-shaped rimmed cases. Future experiments will be made with H380 ball powder when some is secured.
One other load tested:
200 gr. jacketed Nosler partition .323
46.0 gr. IMR 4350
CCI 250 mag. primer
Reworked Graf 7.62x54R cases
Avg. muz. velocity: 1558
Standard deviation: 33.93
Accuracy much better than the same bullet used with H414 powder, data above.
I should add that the temperature at the range today was just above freezing, but the ammunition was kept in the warm car until just before firing.
Added 12-20-05:
I have decided that I am going to stick with the .329/.330 bullets in loading this caliber as these seem to be working the best. Accordingly, I have contacted CH/4D, the makers of the dies, and have enquired about the possibility of opening up the seater die to .330 so I can crimp the case into the cannelure of .330 bullets. We'll see what they say.
"Sehr schwer, mein Herr"
Edited by: gschwertley at: 12/27/05 10:04 pm
txpete
Two Wheeler
Posts: 515
(12/24/05 10:53 pm)
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Re: Still more experiments with the 8x50R
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sure sounds like you have this one shooting good now.thats alot of work to get the ol rifling shooting well.
pete
gschwertley
saddle soap
Posts: 1540
(12/25/05 1:17 am)
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Re: Still more experiments with the 8x50R
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Yes, I think I have homed in on knowing about what I need to know about this one.
I emailed CH/4D about opening up the seating die around 9:00PM one evening. I checked my email account for another reason about 15 minutes later and CH/4D had answered me already, and it was 11:00PM in Ohio where they are located. Imagine that for customer service. Anyway, they will modify the die for me for $5 plus return shipping; that seems reasonable.
My plans are to stick with the H-1000 and the 250 gr. bullets; they seem to be a good combination. I may try some IMR 4831 and some H380 when I get some.
"Sehr schwer, mein Herr"
yockey5
Coffee Pot
Posts: 10219
(12/25/05 6:00 pm)
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Re: Still more experiments with the 8x50R
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Keep us posted Gary, I will soon have to be loading up some of these.
coffee pot
When your firearms are taken, your democracy no longer exists.
junkbug
Registered Member
Posts: 10
(1/4/06 5:21 pm)
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Re: Still more experiments with the 8x50R
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This may sound like an ignorant question, but;
Are you shooting these loads out of a rifle NOT rechambered for 8x56R, ie original 8x50R chambers?
I ask because I am also wondering if it was considered practical and safe, to use old 8x50R cartrides in a modified 8x56R "S" chambered rifle, while these rifles were in actual military use.
I have no surplus 8x50R, but was just wondering.
yockey5
Coffee Pot
Posts: 10395
(1/4/06 6:58 pm)
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Re: Still more experiments with the 8x50R
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Would be a total waste of time and ammo. You would eject scrap from the action, and a squib down range, if it didn't get hung up in the barrel.
coffee pot
When your firearms are taken, your democracy no longer exists.
gschwertley
saddle soap
Posts: 1573
(1/5/06 12:36 am)
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Re: Still more experiments with the 8x50R
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NEVER, EVER shoot 8x50R in a rifle chambered for 8x56R. The blow-back gas escaping rearward from the chamber due to improper fit of the brass case could hurt you.
"Sehr schwer, mein Herr"
junkbug
contributing member
Posts: 11
(1/6/06 4:48 pm)
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Re: Still more experiments with the 8x50R
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Thanks for the replies. Mostly, I was wondering if there is any recorded evidence of this being done in military use, under the pressure of supply shortages. Also, since I have never handled a 8x50R cartridge, I do not know just how different it is from the 8x56R, other than looking at pictures.
Thanks.
Sean
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