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Stickbow, I see now what it was you're talking about - I have some minor leading up there too, gonna go buy a ChoreBoy copper scrub pad, (all copper, no copper washed steel), and wrap that around something to put in the block and spin it. That should do it, same as it does in a bore.
ighter cast bullet, say 135g or so? I have a source for those but haven't found the heavier ones
First off and more importantly, I would like to give a big thanks and deep appreciation to armoredman, robertbank, and seppos for all the helpful advice.
I finally got the opportunity to remove the heavy lead fouling from the gas block of my VZ-58 ( Actually a Century Arms VZ-2008). I spent approx. three hours picking, sanding, heating, and scrapping the inside of the gas block to disperse the heavy lead fouling. Overall, I could have instantly removed the majority of the lead fouling if I would have used a 12 millimeter reamer. I plan to purchase a $14.00, 12mm reamer soon. Never the less, I used pieces of “Chore-Boy” on a cleaning jag, rough sand paper on a stick, and a piece of “Scrubb-Bubba” pad fastened to a long wood screw. All methods worked. Ultimately I had to use a cheap pearing knife with a bent blade (90 degree angle) – plus, a heat gun aimed directly inside the gas block bore. The scrapping action of the knife removed the heat softened stubborn stuff!
Hopefully I don’t get myself in this position again. Unfortunately, I made the mistake of taking too many short cuts. Basically I took a plain base 115 gr. lead bullet and loaded 17.3 gr's of Alliant 2400 behind this plain based pill. I was in to much of a hurry to work up a load that would consistantly cycle the action on my VZ-58. I did not pay attention to bullet hardness or velocity of the 115gr. lead pill.
I will not make a rushed mistake like this agian. I ordered a new mould, a hardness tester, and a thermometer . Plus I have been spending time examining loads on this web site and others. Hopefully within the next 3 weeks I will have all my ducks in a row and I will post my new results for the 7.62x39 cast bullet round.
Thanks Agian Robin M. Smith
Good that it worked out finally.
Dont loose hope with the cast boolits in it. With proper boolit and load it will not lead and you get the best accuracy..
S
Hello everyone;
I loaded and tested a new batch of 7.62 x39 cast boolit loads. Overall, I witnessed improved results, but still disappointed with the lead fouling.
Bore of my VZ58 slugged at .310 groove Dia.
Here are the steps I took:
1) Using a Lee electric furnace, a Saeco hardness tester, and the Lee #CTL312-160-2R mold I casted approx. 500 boolits. I used scrap sheet lead and grade 3 Babbitt to replicate the Lyman #2 alloy. I mixed the Babbitt and sheet lead together until my bullets hardness measured 7 or 8 on the Saeco hardness scale. Which in turn replicates the hardness of Lyman’s #2 alloy. I checked approx. 1 out of 50 boolits for hardness. Fresh unlubed boolits weighed about 155 gr. After the gas check was installed and two coats of lube applied the boolits weighed in at 160 gr.
2) I tumble lubed the boolits with Lee Liquid Alox. I sized and gas checked the boolits to .3115 using a push through die and Hornady .30 cal. gas checks. Afterwards I tumble lubed the boolits again in Lee liquid Alox.
3) For starters, I consulted the Lyman Cast Bullet Handbook 4th edition, Pg. 168. I choose 8.8 grs. Of Unique smokeless powder. I felt this low velocity rated load at 1398 fps would be a good start. I was extremely confident that this particular load would not cause any leading, but I was wrong.
4) My VZ58 was clean. I placed a dab of grease on the front face of gas piston and coated the inside of the gas block with gun oil.
5) I used Lapua brass, 2.117 trim length, CCI large rifle primers, 8.8 gr. of Unique, bullets air cooled from a Lee #CTL312-160-2R mold, bullet hardness 7 to 8 on the Saeco scale, all bullets gas checked and sized to .3115, OAL 2.170. (This load never once cycled the action).
Results; I fired all 50 rounds standing offhand at a distance of 25 yds at Pro Armament in Cuyahoga Falls Ohio. In my opinion accuracy was excellent for shooting in low light conditions with a pair of old man eyes. I like the load because I did not lose any of my brass; I had to cycle the action manually. There was no leading at all inside the barrel, but the inside of the gas block is lead fouled as well as the face of the gas piston. Again, there is absolutely no leading in the barrel, or on the outside diameter of the gas piston (except for a few tiny specks). It seems like the inside of the gas block acts like a lead magnet.
What should I do next? Any advice is welcome. A big thanks in advance to all who read my post!
I suggest that you slug the barrel.. My quess is that there is a metal sprue sticking in the barrel in the side of the gas hole that scrapes some lead from the bullet when it passes the hole.
If you feel resistance when pushing the lead slug thru the barrel, mark the spots to the side of your cleaning rod.. That way you could later on determin the actual places, and after lapping see, if they are gone.
The scraping is also possible to see from the slug..
S
I did find lead fouling in my vz-58 gas block, but not very much. I'll invest in that pick! I decided to pretty much leave it for jacketed stuff for now.
Today I took the CZ 527M out again, and went for it at 100 yards. When I started I said I wanted a cast load that was as accurate as my j-word bullets at 100 yards.
Do you I think I found it?
All rounds fired from the bench, front of the rifle rested.
First, the standard 123gr Hornady soft point load.
http://i16.photobucket.com/albums/b1...at100yards.jpg
Then, adjusted with 5 inch hold over for boolit drop, the cast load, 19.5 grains Accurate #1680 under a NOE sized to .311, lubed with LLA, gas checked, light FCD, COAL of 2.18. Data provided for academic purposes only, of course.
http://i16.photobucket.com/albums/b1...at100yards.jpg
Same load same distance, same everything, have to get corroboration,
http://i16.photobucket.com/albums/b1...at100yards.jpg
Also fired, the Lyman 128.5 grain boolit donated by a great member here, not bad at all,
http://i16.photobucket.com/albums/b1...at100yards.jpg
I think this NOE boolit has shown it can do the job. Once I get the load dialed in, I'll re-zero the scope to that load. BTW, leading? Nary a spot to be found. I like that.:smile:
Time to do some very minor load tweaking, but I think I found it.:holysheep::castmine:
I apply a little grease on the end of the push rod on my SKS. This doesn't eliminate the fouling but it sure does come off easier. You might want to try it on your CZ.
Take Care
Bob
My pony won't trot. I loaded up a few FC cases in 7.62x39 for a Chinese SKS with the Lee 155 boolit sized in a .314" Star die that doesn't really touch the .3125" as cast boolit. I used 14.5 gr.of old Herc 2400 and won't function as a semi auto. So I upped the charge to 15.7 gr. (the next size up in my Lee measure) and while it shoots splendidly it still doesn't quite eject the brass. I do not want to go any higher with 2400, and actually I'd like to stay at this velocity as it does not damage my steel plate targets. Can I buy a bolt spring and start removing coils until it will function?
Duke
Simple solution: go to a slower powder like 1680, N120 or similar.Quote:
Originally Posted by L Ross
In my gas piston 7.62 x 39 AR, the Ed Harris-recommended 16 grains of 1680 ( with the 155 gr Lee bullet) shoots like a dream, but isn't quite enough to cycle 100% reliably. 16.5 grains worked like a charm, EXCEPT: the cases are heavily smoke stained, and there is buckets of unburned powder that even gets deposited around the case deflector.
17, 17.5 and 18 grains of N120 burn cleanly but aren't quite as accurate, and all cycle reliably. 17.5 is best so far, but I'm also going to try going a little lighter.
A full-house load of 26 grains of N130 was not as accurate, and started burning lubricant in an unpleasant manner (I shoot indoors with a muzzle brake, so you can guess the rest...)
Loads are gas-checked and lubricated with Carnuba Red (once I made the switch from 50/50 and BAC I'll never go back to an alox-based lubricant).
Thanks Stoats, I went out and got a pound of AA1680 today and will load some ammo tonight and test until I get functioning.
uke
16 grains of N120 cycles reliably; Best group was achieved at 16.5
AA 1680 is the standard for 7.62x39mm with me.
Hey Armoredman, how fast are you pushing your loads? I find if I hit 1800 fps I start getting target damage on my admittedly mild steel discs and silhouettes.
Duke
AA1680 is extremely dirty when even slightly downloaded. I would take coils off a spring.
That's strange,my Chinese SKS throws the brass 5+ ft. out with only 12.5 grs. of 2400 If I use the 14.5 gr. load I'm looking for the brass out in the yard. All rifles seem to handle the loads differently.
My friend Andy had similar issue with his Russian SKS rifles using 2400,one rifle cycles fine with the 15.0 gr. load while the other two want. I suggested he use the starting load of 18.0 grs. of RX7 and all was well after that and accuracy was excellent.
I did just that in front of 6 grains of Trailboss. Perfect!Quote:
Originally Posted by txpete
BTW, sorry for the 5 month late answer, just saw this. :smile:
its ok I get the same treatment from the wife :-).I'll give that a try in the ruger.thanks.
pete
I like Alliant 2400 for cast loads in my mil surpp rifles. These loads are accurate at the 200 yard range of our vintage military rifle matches and 2400 doesn't seem at all position sensitive for the rapid fire strings of fire. I, however, haven't been able to get Alliant 2400 to work in any of the 3 SKS rifles I've owned; a Russian, a Norinko, and now an Albanian. 15 gr of 2400 and the Lee 155 gr. SKS bullet wouldn't cycle the action. Slower burning powders all seem to cycle fine and since I keep a good supply of IMR 4895 on hand to load for my M1 Garand I use it for my SKS, too. I do wish I could use 2400 as it is so accurate with all my other cast bullet loads in other calibers (and 15 gr. of it would be lots cheaper than 26 grs. of IMR 4895.
My Yugo SKS shoots the group buy "fat 311041" just fine w/1.8cc surplus 4895.
RTL bullet weight = ~180 grs in ac/ww alloy;
Velocity = ~1700 fps;
accuracy = 5/8" @ 50 yards, 3 shots peep sights;
function = 100 % reliable = never yet had a failure to feed or eject. It has also never leaded the barrel or the push rod.
Bullet lube = two coats of LLA. Sized .311" Lee push through.
If ya gotta Yugo, ya oughter try it!! The regular Lyman 311041 works just fine, too. One of these days I'll try the group buy "fat soup can" bullet and see if it'll run at ~2,000 fps.