CZ 527, 7.62x39 success

hoytcanon said:
My fondness for the 7.62X39 cartridge is almost equal to my dislike for the SKS rifle.

In my bolt action rifles I load 130 SP's over 27.5 grains of H4198. I just picked up a couple pounds of CFE-BLK to try, but have no report on it yet.
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hoytcanon said:
I have owned and loaded for dozens of No.1's... I am well versed when it comes to this action... but my point was, that I am currently loading as hot (over capacity, compressed) as the cartridge will allow for my M77... so what powder, charge and bullet equals a "super load" that will do more than what I am currently shooting? Or do you think that because it is a No.1 it somehow increases the load output? How is your hot load "hotter" than my hot load out of your 22" No.1 as opposed to my 22" M77?
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Just higher pressure loads. I'm loading my No.1 at higher than factory load pressure using a heavy charge of propellant X to get considerably higher muzzle speeds. My rifle (only!) seems to safely handle the increased pressure because there are no apparent excess pressure signs.

For reference -

Hodgdon load data online lists 26.5 grs of H4198 with a 125gr .311 bullet at 2378 fps (24" barrel) and 40,400 cup.

Hornady Handbook (7th ed.) lists 25.6 grs of H4198 with a 130gr .308 bullet at 2400 fps (a 20" barrel SKS) and assumed < SAAMI max. pressure for the x39, 50,000 cup.

Your load has about 7% more powder than the Hornady maximum load so with all else being equal (which likely isn't the case) you are likely exceeding x39 SAAMI maximum pressure. By doing so your action and barrel are under greater stress than at SAAMI maximum pressure.

My bolt action x39 has a safe pressure limit but my No.1 action being a falling block seems to have a higher safe limit.
 
Slamfire said:
Just higher pressure loads. I'm loading my No.1 at higher than factory load pressure using a heavy charge of propellant X to get considerably higher muzzle speeds. My rifle (only!) seems to safely handle the increased pressure because there are no apparent excess pressure signs.

For reference -

Hodgdon load data online lists 26.5 grs of H4198 with a 125gr .311 bullet at 2378 fps (24" barrel) and 40,400 cup.

Hornady Handbook (7th ed.) lists 25.6 grs of H4198 with a 130gr .308 bullet at 2400 fps (a 20" barrel SKS) and assumed < SAAMI max. pressure for the x39, 50,000 cup.

Your load has about 7% more powder than the Hornady maximum load so with all else being equal (which likely isn't the case) you are likely exceeding x39 SAAMI maximum pressure. By doing so your action and barrel are under greater stress than at SAAMI maximum pressure.

My bolt action x39 has a safe pressure limit but my No.1 action being a falling block seems to have a higher safe limit.
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As I said, I am shooting a compressed load, from a 22" M77 MKII... the brass shows no signs of pressure, the primer pockets are tight, I have five and six firings on brass, the bolt lift is normal, the fired brass is not sooted up and the chamber is clean... what more can I do as compared to your 22" No.1? I am in the process of testing CFE BLK with 130 SP's... it has been reported that it can increase MV in excess of 100 fps over H4198.
 
x39 SAAMI pressure limit is 45,000 psi which published load data should be in compliance with. Mk II actions are also made in higher pressure chamberings like 7mm-08 for example which has a SAAMI pressure limit of 61,000 psi. Unknown if the Mk II x39 action is identical in every respect to the higher pressure Mk II chamberings. Just need to follow generally accepted safe handloading practices to determine a maximum safe load for your rifle.

http://www.saami.org/specifications_and_information/publications/download/Z299-4_ANSI-SAAMI_CFR.pdf

I would bet my x39 No.1 would safely max out higher than the Mk II action. ;)
 
Slamfire said:
I would bet my x39 No.1 would safely max out higher than the Mk II action. ;)
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A. Who would know... the recipe is safely secured in the depths of Fort Knox.

B. Who cares... if the M77 action safely and easily handles maxed out, compressed loads, the No.1 holds NO advantage.
 
A higher safe chamber pressure should mean higher muzzle speeds. If the objective is higher muzzle speeds then the No.1 has the advantage over a Mk II. As mentioned 123gr SST bullets safely do 2700 fps at the muzzle from my No.1. I would be curious to know what a Mk II can safely do. I'm pretty sure my Mini Mauser can't safely do that, there would definitely be excess pressure signs well before that muzzle speed is reached.
 
They are both SAAMI chambers, and as I said, there is no evidence of excessive pressure with the compressed loads that I am shooting... so why don't you PM your "super load", I promise to "work up" to it in my M77 MKII chambers.
 
Well, its be nice, but I am busy trying to cram a few more crumbs of powder in this little case and still hold a bullet in the neck... maybe I will just fill it, pack it down and glue the bullet on... now where did I put that hot gluegun???
 
okay, so here's a scenario..... yer in a treestand, 20 feet up and shots will be pretty much point blank range to absolute maximum 50 yards...... which load are you going to choose? These are 160 to 200+ pound deer on the hoof. Black bear are a routine passer by at the stand as well.
 
Any good 123-150gr bullet will suffice.I have a box of Barnes .310 123 TSX that I wanted to spank a moose with but happened to be holding my .300 H+H when she waltzed into the field of fire. I'm heading out this am to test some 150gr .311 Sierras and H335 loads seeing I'm tagged out. I want to try the D4198 I purchased soon as well as I'm getting low on H4198 hopefully it's relatively close and workable for the 7.62x39 and my 45-70
 
Super Load;

Now I just have to mount a 6-24X scope on my new long range 7.62X39... OAL @ 2.25"... 7.62X39 flanked by .350 Rem Mag.
 
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sp

The 7.62 x 39 is one of those "the little gun that could" rounds. I'd be happy with a bolt gun that shot that cartridge. And beyond CZ (RH) - Savage manufactured a Model 10 Scout in a LH configuration as did Zastava with the Model 85. I was never aware if there was more then one of each of these rifles ever brought into, and sold in Canada. I missed out on both of them.

I would like to thank the posters who added some meaningful load data on the 7.62 x 39, and I was very interested in the possibilities that were demonstrated on the tables of "the little gun that could". I've always thought (without any real data of my own) that the round was probably good to about 175 yards or so. The data shows that when loaded effectively it could produce terminal results beyond that range.

For what it is - the 7.62 x 39 deserves as much attention as a 30-30 and perhaps more.
 
Well 29gr of H-335 and the Sierra .311 /150gr SP put 3 just under an inch.I'll have to move it on up gradually ,as the warmer it was loaded the tighter the groups became.Lee book calls 29 MAX but some are running 31gr in a CZ 527.
 
I really need to get off my butt and finally start reloading rounds, x39 especially, I am having good luck with hornady SST steel case rounds but reading some of these posts is motivating me to see what some of my rifles can do.

My 7.62x39 guns that I would be loading for are an AIA enfield "jungle carbine", howa 1500 HB mini action and a CZ 527. My 858, SKS's and soon to be T81's all eat surplus, I don't see the point of loading for them, maybe some mexican match but I will save my brass for my bolt guns.
 
Slamfire said:
CFE BLK is #70 on the relative burn rate chart, H4198 is #74 -

https://www.hodgdon.com/wp-content/uploads/2017/09/burn-rate-color.pdf

An interesting round to hot rod (safely!!) for sure. :cool:
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The burn rate chart is not 100% reflective of what a particular powder will do in a particular cartridge with a particular bullet... as I said, early reporting is that with 125/130 grain bullets, CFE BLK is netting an additional 100-150 fps, all else being equal... it.is a denser powder for sure, and I will see what it can do in testing over the winter.
 
Very interesting to see you are using .308 SST's instead of .310 SST's. The .308's will slip down your barrel with less frictional loss than the .310's = higher muzzle speed. I safely load. 310 SST's for a muzzle speed of 2700 fps in my No.1.

I will have to give the .308 SST's a try to see how much of a safe increase in muzzle speed I can get.

37085070970_5f02805c7f_z.jpg
 
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Slamfire said:
Very interesting to see you are using .308 SST's instead of .310 SST's. The .308's will slip down your barrel with less frictional loss than the .310's = higher muzzle speed. I safely load. 310 SST's for a muzzle speed of 2700 fps in my No.1.

I will have to give the .308 SST's a try to see how much of a safe increase in muzzle speed I can get.

37085070970_5f02805c7f_z.jpg
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I am using .308 bullets in this rifle, because it is a Post-Davidson's M77 MKII with a .308 bore. My Davidson's M77 MKII is a .3105" bore and I use .310-.311 bullets in that one.
 
Right, Ruger was using .308 groove diameter barrels for a while in their x39 rifles. I get 2400+ fps muzzle speed with 150gr .308 bullets in my No.1. I'm hesitant to use the same powder charge with 150gr .310/.311 bullets. :eek:
 
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