best powder for CZ527 in 7.62 x39

[JohnnyArtist]

Hi I'm new to forum

Just wondering if anyone has good advice on the best powder to use for a bolt action CZ527 7.62 x39. Bore slugs at .3125 1:9.5 twist.

so far I've tried the following lead loads...

.314 165gr (173gr with GC) 22BHS - 9gr Unique - 1440fps - 4" groups at 300m
.314 116gr ungas checked head 15BHS - 5gr trail boss - 1000fps - 6" at 100yds although .5" at 25yds

I'd like to get the 165g GC head going a little faster and not sure whats happening with the 116gr heads.
Also like to get a jacketed soft point to 1700ftlb (legal for Roe deer in UK) 125gr needs 2500fps and 150gr needs 2260fps.
I've tried Lovex DO63 (similar to 1680) and H335 for the jacketed heads but these seem far too slow for the bolt action with expansion still going on when the bullet is already down range.

How about H110 or N110? too fast??

Hope someone can help any advice would be much appreciated.

John

[Yodogsandman]

For the 165 gr, try Reloader 7, IMR4895 and IMR4227.

I have no experience with a 116gr.

[JohnnyArtist]

Many thanks I'll give IMR4227 a go if I can get it here in the UK

[OptimusPanda]

I've only used imr4198 for that rifle and cartridge combo. Although I plan to try out 2400 and reloder 7, those are next.

[Driver man]

I don't think that cartridge can be pushed to 1700ftlb safely

[JohnnyArtist]

yes 2400 next for me. this was a good piece by C E Harris...
http://www.castpics.net/subsite2/Classics/Cast%20Bullet%20loads%20for%20Military%20rifles.pd f

CAST BULLET LOADS FOR MILITARY RIFLES
Cast bullets can make shooting that surplus rifle easy and economical.And basic data works for many different guns.
BY C. E. Harris
Cast bullet loads usually give a more useful zero at practical field ranges with military battle sights than do full powerloads. Nothing is more frustrating than a military rifle that shoots a foot high at 100 yards with surplus ammo when thesight is as low as it will go! Do not use inert fillers (Dacron or kapok) to take up excess empty space in the case. Thiswas once common practice, but it raises chamber pressure and under certain conditions contributes to chamber ringing.If a particular load will not work well without a filler, the powder is not suitable for those conditions of loading. Fourload classifications from Mattern (1932) cover all uses for the cast bullet military rifle. I worked up equivalent chargesto obtain the desired velocity ranges with modern powders, which provide a sound basis for loading cast bullets in anypost-1898 military rifle from 7mm to 8mm:
1. 125 grain plain based "small game/gallery" 900-1000 f.p.s., 5 grains of Bullseye or equivalent.
2. 150 grain plain based "100-yard target/small game", 1050-1250 f.p.s., 7 grains of Bullseye or equivalent.3. 170-180 grain gas checked "200 yard target", 1500-1600 f.p.s., 16 grains of Hercules #2400 or equivalent.4. 180-200 grain gas-checked "deer/600 yard target", 1750-1850 f.p.s., 26 grains of RL-7 or equivalent.
None of these loads are maximum when used in full-sized rifle cases such as the 30-40 Krag, .303 British, 7.65Argentine, 7.7 Jap, 7.62x54R Russian , or 30-06. They can be used as basic load data in most modern military rifles of7mm or larger, with a standard weight cast bullet for the caliber, such as 140-170 grains in the 7x57, 150-180 grains inthe .30 calibers, and 150-190 grains in the 8mm. For bores smaller than 7mm, consult published data.
The Small Game or Gallery" Load
The 110-115 grain bullets intended for the .30 carbine and .32-20 Winchester, such as the Lyman #3118, #311008,#311359, or #311316 are not as accurate as heavier ones like the #311291. There isn't a readily available .30 calibercast small game bullet of the proper 125-130 grain weight. LBT makes a 130 grain flat-nosed gas-check bullet for the.32 H&R Magnum which is ideal for this purpose. I recommend it highly, particularly if you own a .32 revolver.
The "100 Yard Target and Small Game" Load
I use Mattern's plain-based "100 yard target load" to use up my minor visual defect culls for offhand and rapid-fire100 yard practice. I substitute my usual gas-checked bullets, but without the gas-check. I started doing this in 1963with the Lyman #311291. Today I use the Lee .312-155-2R, or the similar tumble-lubed design TL.312-160-2R. Mostof my rifle shooting is done with these two basic designs.
Bullets I intend for plain based loads are blunted using a flat-nosed top punch in my lubricator, providing a 1/8" flatwhich makes them more effective on small game and clearly distinguishes them from my heavier gas-checked loads.This makes more sense to me than casting different bullets.
Bullet preparation is easy. I visually inspect each run of bullets and throw those with gross defects into the scrap boxfor remelting. Bullets with minor visual defects are tumble-lubed in Lee Liquid Alox without sizing, and are used forplain base plinkers. Bullets which are visually perfect are weighed and sorted into groups of +/- 0.5 grain for use in200 yard matches. Gas checks are pressed onto bullet bases by hand prior to running into the lubricator-sizer. For gas-check bullets loaded without the gas- checks, for cases like the .303 British, 7.62 NATO, 7.62x54R Russian and 30-06,




I use 6-7 grains of almost any fast burning powder. These include, but are not limited to Bullseye, WW231, SR-7625,Green Dot, Red Dot or 700-X. I have also had fine results with 8 to 9 grains of medium rate burning pistol or shotgunpowders, such as Unique, PB, Herco, or SR-4756 in any case of .303 British or larger.
In the 7.62x39 case, use no more than 4 grains of the fast burning powders mentioned or 5 grains of the shotgunpowders. Theses make accurate 50 yard small game loads which let you operate the action manually and save yourprecious cases. These plinkers are more accurate than you can hold.
Repeated loading of rimless cases with very mild loads results in the primer blast shoving the shoulder back, unlessflash holes are enlarged with a No. 39 drill bit to 0.099" diameter. Cases which are so modified must never be usedwith full powered loads! Always identify cases which are so modified by filing a deep groove across the rim andlabeling them clearly to prevent their inadvertent use. For this reason on I prefer to do my plain based practice shootingin rimmed cases like the 30-30, 30-40 Krag, 303 British and 7.62x54R which maintain positive headspace on the rimand are not subject to this limitation.
The Harris "Subsonic Target" Compromise
Mattern liked a velocity of around 1250 f.p.s. for his 100 yard target load because this was common with the leadbullet .32-40 target rifles of his era. I have found grouping is best with non gas- checked bullets in military rifles atlower velocities approaching match grade .22 long rifle ammunition. I use my "Subsonic Target" load at around 1050-1100 f.p.s. to replace both Mattern's "small game" and "100 yard target" loads, though I have lumped it with the lattersince it really serves the same purpose. It's report is only a modest "pop" rather than a "crack".
If elongated bullet holes and enlarged groups indicate marginal bullet stability, increase the charge no more than a fullgrain from the minimum recommended, if needed to get consistent accuracy. If this doesn't work, try a bullet which ismore blunt and short for its weight because it will be more easily stabilized. If this doesn't do the trick, you mustchange to a gas-checked bullet and a heavier load.
The Workhorse Load - Mattern's "200 yard Target"
My favorite load is the most accurate. Mattern's so-called "200 yard target load." I expect 10 shot groups at 200 yards,firing prone rapid with sling to average 4-5". I shoot high Sharpshooter, low Expert scores across the course with anissue 03A3 or M1917, shooting in a cloth coat, using may cast bullet loads. The power of this load approximates the32-40, inadequate for deer by today's standards. Mattern's "200 yard target load" is easy to assemble. Because it is amild load, soft scrap alloys usually give better accuracy than harder ones, such as linotype. Local military collector-shooters have standardized on 16 grains of #2400 as the "universal" prescription. It gives around 1500 f.p.s. with a150-180 grain cast bullet in almost any military caliber. We use 16 grains of #2400 as our reference standard, just ashigh power competitors use 168 Sierra Match Kings and 4895.
The only common military rifle cartridge in which 16 grains of #2400 provides a maximum load, and which must notbe exceeded, is in the tiny 7.63x39mm case. Most SKS rifles will function reliably with charges of #2400 as light as 14grains with the Lee 312-155-2R at around 1500 f.p.s. I designed this bullet especially for the 7.62x39, but it worksvery well as a light bullet in any .30 or .303 caliber rifle.
Sixteen Grains of #2400 is the Universal Load
The same 16 grain charge of #2400 is universal for all calibers as a starting load. It is mild and accurate in any largermilitary case from a 30-40 Krag or .303 British up through a 30-06 or 7.9x57, with standard weight bullets of suitablediameter for the caliber. This is my recommendation for anybody trying cast bullets loads for the first time in amilitary rifle without prior load development. I say this because #2400 is not "position sensitive", requires no fiberfillers to ensure uniform ignition, and actually groups better when you stripper-clip load the rifle and bang them off,rather than tipping the muzzle up to position the powder charge.




Similar ballistics can be obtained with other powders in any case from 7.62x39 to 30-06 size. If you don't haveHercules #2400, you can freely substitute 17 grains of IMR or H4227, 18 grains of 4198, 21 grains of Reloder 7, 24grains of IMR 3031, or 25.5 grains of 4895 for comparable results.
However, these other powders may give some vertical stringing in cases larger than the 7.62x39 unless the charge ispositioned against the primer by tipping the muzzle up before firing. Hercules #2400 does not require this precaution.Don't ask me why. Hercules #2400 usually gives tight clusters only within a narrow range of charge weights within agrain or so, and the "universal" 16 grain load is almost always the best. Believe me, we have spent a lot of time tryingto improve on this, and you can take our word for it.
The beauty of the "200 yard target load" at about 1500 f.p.s. is that it can be assembled from bullets cast from thecheapest, inexpensive scrap alloy, and fired all day without having to clean the bore. It always works. Leading is nevera problem. Once a uniform bore condition is established, the rifle behaves like a .22 match rifle, perhaps needing awarming shot or two if it has cooled, but otherwise being remarkably consistent.
The only thing I do after a day's shooting with this load is to swab the bore with a couple of wet patches of GI borecleaner or Hoppe's, and let it soak until the next match. I then follow with three dry patches prior to firing. It takesonly about three foulers to get the 03A3 to settle into tight little clusters again.
"Deer and Long Range Target Load"
Mattern's "deer and 600 yard target load" can be assembled in cases of 30-40 Krag capacity or larger up to 30-06 using18-21 grains of #2400 or 4227, 22-25 grains of 4198, 25-28 grains of RL-7 or 27-30 grains of 4895, which give from1700-1800 f.p.s., depending on the case size. These charges must not be used in cases smaller than the 303 Britishwithout cross checking against published data! The minimum charge should always be used initially, and the chargeadjusted within the specified range only as necessary to get best grouping.
Popular folklore suggests a barrel must be near perfect for good results with cast bullets, but this is mostly bunk,though you may have to be persistent.
I have a rusty-bored Finnish M28/30 which I have shot extensively, in making direct comparisons with the samebatches of loads on the same day with a mint M28 and there was no difference. The secret in getting a worn bore toshoot acceptably is to remove all prior fouling and corrosion. Then you must continue to clean the bore "thoroughlyand often" until it maintains a consistent bore condition over the long term. You must also keep cast bullet loads under1800 f.p.s. for hunting and under 1600 f.p.s. for target work.
A cleaned and restored bore will usually give good accuracy with cast bullet loads if the bullet fits the chamber throatproperly, is well lubricated and the velocities are kept below 1800 f.p.s.
The distinction between throat diameter and groove diameter in determining proper bullet size is important. If you areunable to determine throat diameter from a chamber cast, a rule of thumb is to size bullets .002" over groove diameter,such as .310" for a 30-06, .312" for a 7.63x54R and .314" for a .303 British.
"Oversized 30's", like the .303 British, 7.7 Jap, 7.65 Argentine, and 7.62x39 Russian frequently give poor accuracywith .30 caliber cast bullets designed for U.S. barrels having .300 bore and .308 groove dimensions. This is because thepart of the bullet ahead of the driving bands receives no guidance from the lands in barrel s of larger bore diameter.The quick rule of thumb to checking proper fit of the forepart is to insert the bullet, nose first, into the muzzle. If itenters clear up to the front driving band without being noticeably engraved, accuracy will seldom be satisfactory.
The forepart is not too large if loaded rounds can be chambered with only slight resistance, the bullet does nottelescope back into the case, or stick in the throat when extracted without firing. A properly fitting cast bullet shouldengrave the forepart positively with the lands, and be no more than .001" under chamber throat diameter on the drivingbands. Cast bullets with a tapered forepart at least .002" over bore diameter give the best results.




Many pre-WWII Russian rifles of US make, and later Finnish reworks, particularly those with Swiss barrels by thefirm SIG, have very snug chamber necks and cannot be used with bullets over .311" diameter unless case necks arereamed or outside turned to .011" wall thickness to provide safe clearance.
Bullets with a large forepart, like the Lee 312-155-2R or Lyman #314299 work best with the 7.62x54R because theforcing cones are large and gradual. Standard .30 caliber gas-checks are correct.
Finnish 7.62x54R, Russian 7.62x39 and 7.65 Argentine barrels are smaller than Russian 7.62x54R, Chinese 7.62x39,Jap 7.7 or .303 British barrels, and usually have standard .300" bore diameter. (Finnish barrels occasionally are assmall as .298") and groove diameters of .310 -.3115".
In getting the best grouping with iron sighted military rifles, eyesight is the limiting factor. Anybody over age 40 whoshoots iron sights should equip himself with a "Farr-Sight" from Gil Hebard or Brownell's. This adjustable aperture foryour eyeglass frame was intended for indoor pistol shooters, but it helps my iron sight rifle shooting, and adds about 5points to my score!
So now you have enough fundamentals to get started. If you want to have fun, give that old military rifle a try. You'llnever know the fun you've been missing until you try it!

[Coopaloop86]

I'm using Shooters World powder which is Lovex in a Norinco SKS and getting great results. 23 grs of Lovex D073-01 which is Shooters World "Tactical Rifle" is giving me 1850fps with a Lee 155gr ACWW sized and GC at .314 and coated with Hi-tek. Shooting 2 inch groups with iron sights at 100 yards. Also D063-02 at 22grs with the same load performs equally as well.

[marlin39a]

For Jacketed in 7.62x39 I go to Accurate 1680. For lead its 2400.

[JohnnyArtist]

Thanks
So would about 15gr of 2400 165gr GC head be good to start at?

[runfiverun]

the european N-110 is pretty close to our 2400.
the AA-1680 is about 2 steps slower than 2400 and works pretty much where it does you just have to use more.
[I used 4 grs more in the 30-06 to get the same velocity]
Vitaviuri puts out a load data book showing N-110's use for cast loads.
[H-110 is not even close to N-110]

the 1680 will get you to about 2100 fps in a 20" barrel with a 150gr bullet.
you might be able to go a bit slower than 4198 and gain a bit more velocity in a longer barrel.

[Yodogsandman]

Thanks
So would about 15gr of 2400 165gr GC head be good to start at?

"The only common military rifle cartridge in which 16 grains of #2400 provides a maximum load, and which must notbe exceeded, is in the tiny 7.63x39mm case. Most SKS rifles will function reliably with charges of #2400 as light as 14grains with the Lee 312-155-2R at around 1500 f.p.s." C.E. Harris

Maybe try 13 gr 2400 and work up slowly, looking for signs of excess pressure. I would not expect to get the velocity you want without exceeding safe pressure levels with 2400. A slower powder will be wanted.

[JohnnyArtist]

Thanks for everyones input, much appreciated.