CZ-527 7.62x39

[JDL]

They sent a stronger mainspring for mine and all misfires disappeared. These little rifles are just too much fun and will sure put the whomp on armadillos! I use a 165 grain boolit that's from a Mountain Molds mold together with surplus 4895 or WC-844 that runs them about 1900 fps. I keep telling myself to get rid of all the excess baggage and just use this for everything including deer. Yea, like that's going to happen!
JDL

[onondaga]

Your groups are tightening up! looking good. I have two more workup loads to shoot up. The A2230 powder for the X39 is not looking outstanding on paper yet. This is disappointing as I bought a pile of it. Showing no pressure signs for me at 1/2 grain below listed max. MAX loads are in the box to range next. They are 100% capacity right to the base of the neck where my gas check is just contacting. Group size has remained constant in this work-up. Hoping for a dip. I will go past MAX and compress loads if I get no pressure signs. The creep and heavy trigger pull may be what is limiting me. All my other rifles have excellent crisp trigger pulls that are quite light.

Worst news here is that 2 local gunsmiths won't do trigger work on Biakals and the third estimated $120.00 for zero creep and 3# pull on my rifle for polishing/refit all action parts and re-cut new sear angles. This is not happening with my SS check. I was hoping for $40.00, but all my old smiths are dead. I am real tempted to buy my own mainspring compressor and tackle the job myself.

Hope you get your mainspring quick.

Gary

[excess650]

Gary,
Have you tried magnum primers with that ball powder?

[NoDakJak]

onandaga: My load testing with my Remington Spartan (Biakal) has been limited until I can do something with the trigger. It must have a pull in excess of twenty pounds. I hate trigger work but guess that I am going to finally attempt it myself.
My favorite load in my CZ 527 is with the Lee bullet with 16.5 to 18.0 grains of 1680. My barrel mikes at .311 and I size and lube to .312 with Hornady Alox. I have a Modern Bond mold that casts a 140 grain spitzer tht I want to try. A friend uses Lyman 31141 and 4895 to good effect. Works well on deer.
Neil

[onondaga]

Check your PMs. I sent you one on the trigger problem.

Gary

[onondaga]

I am not familiar with the CZ bolt strip down or if you need a specific tool to take it down. Look into that. Cleaning a bolt out and high shining the firing pin can make a big difference, Oil the pin with Triflon or a good oil with teflon after cleaning /polish.

Haven't tried magnum primers. My ignition has been 100% for 200 rounds in bitter cold here so I'm not worried I'll need magnum primers with the ball powder. All My X39 brass was purchased new Winchester brand.

I think we both have good bullet diameters to work with also. Keep shootin! I just loaded some compressed loads with H4895. Had no pressure signs 1/2 grain lighter. I have a chronograph, but won't be clocking till I get the group size I want. This load should be at about 2150 fps, right where I want to be !!! I am going to work past that with all my powders and hunt with the best one. So far H335 is what my rifle likes the best. The last resort trick I have is H380. It will work but there is no data so far. I will research that some more.

Gary

[NHlever]

I am not familiar with the CZ bolt strip down or if you need a specific tool to take it down. Look into that. Cleaning a bolt out and high shining the firing pin can make a big difference, Oil the pin with Triflon or a good oil with teflon after cleaning /polish.

Haven't tried magnum primers. My ignition has been 100% for 200 rounds in bitter cold here so I'm not worried I'll need magnum primers with the ball powder. All My X39 brass was purchased new Winchester brand.

I think we both have good bullet diameters to work with also. Keep shootin! I just loaded some compressed loads with H4895. Had no pressure signs 1/2 grain lighter. I have a chronograph, but won't be clocking till I get the group size I want. This load should be at about 2150 fps, right where I want to be !!! I am going to work past that with all my powders and hunt with the best one. So far H335 is what my rifle likes the best. The last resort trick I have is H380. It will work but there is no data so far. I will research that some more.

Gary

Gary, if you send me a PM with the components you want to use, I can run them through Quick Load for you. You still would need to exercise caution of course, but it would give you a place to start. QL will give expected pressures, and velocities too if you include the barrel length, etc. On the other side of this 7.62x39 loading game, it makes a very good 32-20 with 8 grains of Unique behind a 115 grain boolit. Feeding is no issue with your single shot, but since CZ changed the magazines some years ago, the Lyman 311008, and 311316 fed very well indeed.

[excess650]

I'll try more powder.

[JDL]

The only loads I didn't have misfires with, before going to the stronger mainspring, was Lapua. These cases never varied on on length from the case head to the datum line. All other brands I measured differed as much as .006". Wolf was the worst offender but, Winchester differed up to .004".
JDL

[GBCAPT]

I just got a new 527 carbine in 7.62 X 39 and am figuring out how I want to set it up. I plan to use it to swat coyotes and deer in thick, but small woodlots here in Maine.

I contacted New England Custom Gun who imorts some nice aperature sights that utilize the reciever grooves on Ruger, CZ-550 and Tika rifles. They advised that they have a model in the works for the CZ-527 and hope to have them in inventory by mid-summer.

I find an aperature sight easier to use once one becomes accustomed to it, and the longer sight radius resulting from the sight being on the receiver instead of on the barrel contributes to improved precision.

No price point at this time, but I plan to check back later.

[excess650]

.311" sizing.

[excess650]

Gbcapt,

[onondaga]

The Lee Collet neck size die will need another part for cast bullets. Here Is The response I just got from Lee:

Mr. xxxxxxxx:

The 7.62x39 Collet Die Set includes the Mandrel for .308 bullets but to size the neck for .311 or .312 bullets you would be able to use the 303 British Mandrel. The part number for the Mandrel is NS2628 and costs $4.00.

Thank You
Lee Precision

I can also tell you that the new mandrel will be too long and require shortening to the length of the one supplied with the die.

Gary

[whopist]

Onondaga
If you do the Lee Collet Die .312 mandrel modification, please share procedure and results with us.

Everybody
I too had misfires in my 2007 CZ 527M in x39. CZ sent me a stronger main spring and it, (along with a good cleaning) solved my misfire problem. The new stronger spring was a lot harder to install on the bolt.

Someone on the web posted a procedure to fabricate a spring spacer to make spring tension greater. Just another idea.

Good luck

[JDL]

I have only the LCD for my 527 and modified it so that it doesn't size all the way but, leaves about 1/16ths inch of the mouth unsized. No need for an M die!
I don't think the mandrel is all that important for boolits unless the case mouth is exceedingly misshaped. I adjust mine so I have the proper tension for the size boolit I'm using and use that process for 7.62x39, .30-30, .30'06, and 7.5 Swiss.

JDL

[excess650]

JDL,
Thanks for that bit of info.

[onondaga]

I am saving up for the Lee Collet neck sizer and the .303 Brit mandrel. Full length sizing I can only get 27 grains of H380 into the 7.62X39R and that is a slightly compressed 102% load. Not happy about that because H380 is a nice low pressure powder for cast bullets and 30 grains bulges the base of the neck. I had to unload the single round I tried in a test loading and back off, H380 powder doesn't compress well.

Next month I will order the new Collet die and mandrel and report on it. Neck sizing only will significantly increase the case volume available for this low pressure powder.

Gary

[excess650]

here tomorrow.

[onondaga]

Sounds like the H322 is getting you where I want to be with my 7.62X39Rs. A reduced load calculator says 25.6 Gr H332 = 2150 fps. That is what I'd like for deer hunting with that bullet.

Reduced Load Calculator link:

http://www.handloads.com/calc/reduced.asp

I will have to try that powder if I run out of options here without getting an accurate load at 2150 fps. I am looking for less than 1 inch at 50 yards. My best results have been at just over an inch at that velocity with H4895.

Gary

[dualsport]

I feel like the bastard step child as my bolt 7.62x39 is just an older Mini MK X.......can I play?

Larry Gibson

My 7.62x39 is an H&R single shot. It likes the Harris designed Lee CTL-312-160 2R and a brisk load of WC844. So far 2" groups at 100 yds. are repeatable, I'm hoping to refine that some. I had a Mini Mk X in .223, most accurate rifle I've ever shot. That was in the 80s, the thing was a work of art. Hit a dime everytime at 100 yds. with Winchester hollow points. I am very very sorry I sold it. On a side note, speaking of Lee collet dies, my .303 LCD also neck sizes 7.62x54R very nicely.