First cast bullet loads......

[lcg119]

Well, OK, I am about to embark on an adventure through the world of cast boolit shooting. I have been itching to try some hardcast bullets in my old Yugo M48. This particular rifle likes softball loads...and I have worked up a number of them, using light charges of surplus powder, dacron filler...and various bullets (heretofore, always jacketed bullets). So, now I will try some cast bullets. I have gotten some for the .32-40....sized .323" (170 grains), for a first try. I have pan-lubed them with Lee Liquid Alox, which seemed to work nicely (they were pre-lubed anyway, so the lube grooves are filled with a lube suitable for smokeless powder). These are not gas-checked bullets.....I know, I know, gas-checked would be better...but I want to at least TRY these first, as they are very inexpensive. I have several good jacketed-bullet loads in the range of 26 - 27 grains, using surplus Yugo military flake powder....which behaves like a medium-speed powder. These loads all include a 1/2" square x 1/4" thick pc. of dacron fibrefill, to hold the powder in place. Thus far, after shooting more than 500 rounds loaded in this manner....I have had ZERO problems. Of course, I am mindful of the potential dangers of this...but, as I said, I've had no problems of any kind. I am aware that it would probably be best to push the non gas-checked hardcast bullets at speeds not to exceed perhaps 1200 fps....so I will try for this speed range.

I chose .323" diameter bullets because I assumed that, using the Liquid Alox, that the final end product will be at least .324" in diameter (I have read that most rifles are more accurate with cast bullets .001 - .002 oversized). My bore slugs at just a bit over .323".....approx. .3232", to be exact. I have completed some calculations...and with a bit of estimation thrown in.... I have decided to start at 16 grains of powder....and slowly work up to about 23 grains, as a maximum. According to my calculations/ estimates...this should give velocities in the range of 1000 - 1500 fps.

Of course, as I work up, I will watch closely for signs of problems, especially lead fouling in my barrel. My real question is....for all of you experienced cast boolit shooters.... HOW will I tell if lead deposition is becoming excessive, as velocity increases ? I will not be able to recover any bullets, so examining fired bullets is not a doable procedure. I certainly intend to keep the velocity as modest as possible, while simply looking for a load which is accurate, at 50 yards. I have no intention of pushing the bullets any faster than needed. If I do find any accurate combinations with this bullet, I will likely switch to Unique, or some similar powder, for future use. Right now, I will try what I have on hand. Is it possible to SEE lead fouling, by examing the bore closely....or is it a matter of having whatever accuracy there is suddenly degrade, as fouling becomes a problem? I am hoping that the combination of the Alox lube and the dacron filler will protect the bullet bases from excess gas-cutting....and so may reduce the leading problem. Is my thinking logical on this, or am I fooling myself ? Anyone else try similar experiments....and can you supply any "pointers" ?

I would be most grateful for the benefit of other's experience in this matter.

[singleshotbuff]

icg,

Not on topic about your exact question, but I too use Yugo powder that I pulldown myself. If I may ask, what year is the headstamp of the ammo you're pulling down? (assuming you're pulling it down yourself) Also, is it 198gr FMJ BT? The lot that I have been working from is 198gr FMJ BT and 41.0grs of the flake powder. I have used quite a bit of the pulled down powder and projectiles. I'm just curious as to your tests/results with this powder.

FWIW, I shoot an M48 as well.

SSB

[Bret4207]

Check the muzzle for a "lube star" which looks like a ring of grease around the muzzle lining up with the grooves and lands. That'll at least tell you if the lube is lasting to the muzzle. As far a telling if your getting leading, start with a clean barrel and have a look up it. After your first shot have a look again. You'll notice some residue probably and maybe a little unburned powder. Pay attention to the lands and grooves. If you start to notice streaks of a darker color than the bore thats probably lead. It will remove easily with some 4/0 steel wool or copper Chore Boy wound around an old bore brush.

[lcg119]

Thanks for the replies.

Singleshotbuff, I am using Yugo flake powder that I recovered some time ago....I think this batch was dated 1952....but I am not certain. Yes, this powder is from 50's era Yugoslav 8mm Mauser ammo, with the 198 gr. FMJ BT bullets. As it happens, the standard charge weight in the rounds I pulled down (for this batch of powder) was approx. 41.0 grains also, with a total variance of about .6 grains, plus or minus. I like using this powder....it has proved to be very consistent...and seems like a medium-speed powder, much like IMR-4895. My particular M48 (a "parts" gun, with no numbers matching and very tight headspace) happens to NOT like the standard Yugo load very much....so this is how I began experimenting with this ammo. This rifle seems to like light loads (with the Yugo powder) best....but it behaves a bit differently with cannister powders. It is dead-nuts accurate with a charge of 27.0 grains of the Yugo powder, with .4 grains of the dacron filler added, under the 198 fmj BT bullet. This is the best combination I have ever found, with the Yugo powder and bullet. This load gives great results, often sub 1-inch (when I am shooting well)...with no signs of unburned powder to speak of...and just a little residue on the outside of the case necks. I estimate that this load produces about 1500 fps. Another good load for me is 26.0 grains of the YUgo powder, with the dacron filler....under a 185 grain Remington SP bullet. This is accurate also, but too slow for hunting. With cannister powders, such as IMR-4895 or 4064, mid-range loads perform best....so I use the cannister powders exclusively for hunting. I have never found ANY loads at the hot end that perform well in this rifle. Others I know have had different experiences, so it is obvious that my M48 is just a bit eccentric, as it were.

As for negatives with the Yugo flake powder...I can only report that the pressure curve with this powder increases alarmingly fast, in loads ABOVE 41 grains. The original specs on the Yugo ammo were about 2360 fps at 42,600 psi (so the Yugo rounds are not maximum loads, anyway). I experimented recently with some 170 grain jacketed RN bullets (Hornady)....starting at 41 grains...and working up to 44 grains. Above 42 grains, even with the (14 % lighter) 170 grain bullet, the loads were showing signs of high-pressure. 44 grains was definitely over-pressure. So, I would say, be VERY careful if you ever use this powder to develop loads near the maximum end of the scale. It seems to work very well in light loads, however, but I wouldn't try a charge below about 30 grains without using the dacron filler, to be safe. As I said, I believe that the Yugo powder is a medium-speed powder....and the steep pressure curve above 41 grains tends to support this. It might be safe to download below 30 grains without filler, but I won't try it.

I would be interested in your experiences with the Yugo powder, as well. I have about 3 lbs of it on hand, which I am using up slowly (a lb of powder goes a long way with 27 grain loads). I will try this powder with the hardcast bullets, as well...as I am sure of it's behavior in small charges and with the dacron filler. I expect to prepare some loads...and perhaps begin testing the hardcast bullets this weekend.

Thanks, Tpr. Bret, for the (cast bullet) tips. I will do just as you have suggested.

[singleshotbuff]

ICG,

I have been using this powder, mine is from ammo headstamped 11-54, mostly with the 198gr FMJ and the Rem 185gr bullet you mentioned. I haven't loaded as light as you, I have been in the 30-38gr area. I will try some of your lighter loads with the dacron filler. I have killed 1 deer with the 185gr Rem with 38grs of this powder. I shot kill at 20 yards LOL.

I have chronographed the following from my M48;

Yugo surplus 198gr ave. velocity:2317 f.p.s.

198gr FMJ BT with 35grs pulldown powder ave. velocity: 2076 f.p.s.

198gr FMJ BT with 36grs pulldown powder ave. velocity: 2119 f.p.s.

I can't locate my chronograph data with the 185gr Rem right now, I'll dig it up and post it.

I think your estimate for the 27gr load @1500 f.p.s. is pretty darn close.

SSB

[lcg119]

Singleshotbuff,

Thanks for the info ! I am somewhat amazed at your deer kill (even at 20 yds)....with only 38 grains of powder and the Rem. 185 bullet. Of course, 20 yards is very close, so I suppose that not much is required of a bullet, at that range. I originally "adopted" this bullet for hunting....for several reasons, not the least of which was that it was pretty accurate and comparatively cheap. However, I was worried about velocity and expansion. So, I contacted Remington. They told me that this bullet was actually designed for the 8mm magnum...and that it would not be a good idea for the velocity at POI to be less than about 2400 fps....to ensure adequate expansion. Since this did not give a very wide margin of velocities to work with in the 8 x 57JS cartridge (max. velocity with most powders and this bullet, in the 8mm Mauser, is about 2700-2800 fps...before excess pressure appears).... I decided to not use these bullets for hunting. 20 yards is a rather close shot, whatever the load combination. I wonder, did you recover the bullet....and did it expand at all ?
Your bullet would probably have been traveling at roughly 2300 fps at POI, I estimate. I believe, if I am remembering correctly, that my M48 liked a load (I tried) with this bullet and the Yugo powder in this region of charge weights (35 - 40 grains).
I use my M48 with iron sights only, so hunting distances are never more than 125 yards for me, usually less.

I would be keenly interested in your take on how the (Remington) bullet performed in this case. Thanks very much for the chrono data, as well. I will plug these numbers into my ballistic graph on the 198 grain bullet.

[singleshotbuff]

icg,

I did not recover the bullet, but upon autopsy, the wound channel did show signs of slight expansion. I was impressed with how quickly the young button buck expired (lights out before he hit the ground) but this was an extremely close shot, and of course is only a sample of one.

I looked through my records and can not locate my chronograph data with this bullet. I may try to run some other loads accross the chrony tomorrow, and if I do I'll run a few of these loads as well and post my results.

I did find some chronograph data with a Hornady 150gr bullet and IMR-4320 powder, just forthe sake of conversation;

52grs IMR-4320, 150gr bullet ave velocity: 2781 f.p.s.

53grs IMR-4320, 150gr bullet ave velocity: 2837 f.p.s.

I'll let you know when I have more chronograph data with that pulldown powder.

BTW, what "medium speed" powder do you fell this powder is close to? I've not bothered to look.

SSB

[lcg119]

IMHO, the Yugo powder is somewhwre in the middle of the range....perhaps similar to IMR-4895, H4895....or Varget. Of course, this is only conjecture on my part....it certainly isn't scientific. The Yugo powder does NOT seem to behave as if it were a really slow powder, though....nor a really fast one....so I assume that it is in the middle of the range.

[Buckshot]

"Is it possible to SEE lead fouling, by examing the bore closely....or is it a matter of having whatever accuracy there is suddenly degrade, as fouling becomes a problem? I am hoping that the combination of the Alox lube and the dacron filler will protect the bullet bases from excess gas-cutting....and so may reduce the leading problem."

As Tpr Brett mentioned, when things are going well you'll see a lube star at the muzzle. You'll also see that the lands and grooves will be rather dark looking. As the velocity increases the lube star will begin to diminish. At some point it may disappear and the tops of the lands will begin to lighten in color and probably also the center of the grooves will begin to get a dull silver.

At this point you may notice that your groups are beginning to grow. At the first notice of group enlargement run a damp patch through the barrel and examine it under a bright light. If there are little bright sparkles in the residue then the alloy is reaching it's limit for the load or bore condition.

As you continue the entire bore at the muzzle will display the same dull silver color and the lube star will have long since disappeared. At this point a damp patch may show actual flecks and/or streaks of lead on it. Your group size has no doubt doubled in size. The condition of the bore will have a large part of how fast you can go.

Things to mitigate leadng and increase your velocity potential is to first go to a GC design if you weren't using one before. Also increasing lead hardness and going to a more suitable lube, or more of it will be positive moves. However, it's assumed you're using a boolit that fits the throat, in the first place.

Usually for the highest velocity you'll be using powders normally considered slow for cast boolits and the faster end of the slow burners for high velocity jackest ammo. Probably 4895 will be the fastest of this group of powders.

.................Buckshot

[BerdanIII]

I use Yugo pulldown powder too, and your 26.0 grain load with the 185-gr. Remington bullet is a favorite of mine. The first time I tried it, the extreme spread for velocity was 9 fps and no other load has been as accurate in my rifle (a Spanish M43). Velocity was about 1570 fps and 1540 fps with a Czech 181-gr. S.m.E. bullet. Accuracy with the Czech bullet was so-so; 4 to 5 inches at 100 yards.

I think you will find that 16 grains is too low a starting point; with the 181-gr. BTFMJ, 16.2 grains gave an average velocity of 978 fps and left unburned powder in the bore. With lead bullets being slippery, I would expect even more unburned powder. For the record, my lot of Yugo has a charge weight of 44.1 grains. With 170-grain bullets, you may want to start with 24 grains or so.

You might find that your bullet is too small at .323" and that .325" or .326" might be better. Bullets of .310" diameter work best in my .308, and even .312" bullets chamber with no problem. .308" bullets work, but they're just not as accurate, even at 50 yards; 3" groups being normal. You might be able to patch your bullets with Teflon tape to make up the extra 0.002".

Post your results.

[lcg119]

BerdanIII,

I intended to start with a low charge of the Yugo powder (about 16 grains), because I am testing a plain-base bullet....and I am worried about leading problems. I understand what you mean about unburned powder issues...hopefully, the dacron filler I am using will up the chamber pressure enough to help with this (and it will hopefully help to protect the base of the bullets). Perhaps not. I am a beginner with CB's....so I am leery of jumping in with both feet, without some experimental data. Part of the problem is that I have read conflicting reports as regards to maximum velocity possible with PB bullets.....some say shoot them at no more than 1200 fps...others say that up to 1600 fps is possible, without leading problems. So I will try to err on the side of caution, certainly at the beginning.

I have thoroughly lubed my bullets with Liquid Alox (three times)...and I have loaded 35 of them, starting at 17.0 grains (of the Yugo flake powder)....and up to 23.0 grains, in 5-round lots. I have taken note of your suggestion to start at 24 grains....but I am just not sure about the leading/ bullet lube situation, as of yet. If the 23 grain loads will not produce leading problems in my rifle, with the LLA lube, then I will work up from there.

I'm aware that the .323" bullets may be too small to do well in my rifle.... I decided to try them, just to get some CB experience under my belt (they are cheap). I have always heard that most rifles shoot better with CB's .001" to .002" oversized....and I will certainly go to the larger bullets, as needed. I thought perhaps that the .323" bullets, lubed several times with the Alox, might fit well enough to work well... but, of course, I may be quite wrong about this. I'll see what happens.

In any case, I have taken note of all of the good advice offered by all here. Thanks very much - I am grateful. I will definitely post my results and observations.

[BerdanIII]

Leading really isn't a big problem; if it occurs you can get it out with a couple of patches. In the worst cases, you might have to use a brass brush. I have found that if I lightly pre-lube the bore with a black powder lube like CVA Grease Patch or Spit Lube, the rifle settles down a little sooner and leading hasn't been a problem with the light loads (7 - 8 grains of Unique / 165-gr. plain base in the .308 WCF) I am using. I once cleaned a badly-fouled .303 with cast bullets treated with the black powder lubes above. A couple of shots removed all the leading and black-powder fouling from the bore.

Good luck with your tests.

[singleshotbuff]

Icg,

I ran a samll test on this Yugo pulldown powder today, to attempt to peg down it's burning rate. I thought you might find it interesting, assuming your lot is even close to my lot. I loaded (in 7.5X55mm) the load below, using identical charges of the pulldown powder and IMR-4895 and then ran 10rds of each over the chronograph.

Primer: WLR
Powder: Yugo pulldown & IMR-4895
Charge weight: 20grs
Boolit: 160gr cast LRN, sized .309"

Pulldown average velocity: 1573 f.p.s.
IMR-4895 average velocity: 1263 f.p.s.

As you can see, at least in this application, my lot of this powder is about 300 f.p.s. "faster" than 4895.

Just thought you might find this comparison interesting, for informational purposes.

SSB