The relationship of bhn, velocity, and expansion with cast

Brad

Benevolent Overlord and site owner
Staff member
You passed?
Like Ian said, play with alloy and heat treating. And yes, keep stuff labeled really well. I have a bunch of little zip.oc bags of bullets with notes written on them. This like alloy, heat trat, and the date quenched. Keeps me from having bins of bullets where I don't remember what is what. Yes, I have done that too. It doesn't work out so well.
 

Rick

Moderator
Staff member
I would be very interested in what the "good accurate load" for M1A is. I just started working with mine and have made some improvements from the first loads but not what I would call a good accurate load. Mine is not the National Match but I think it should do better than I have so far.

Ok, thread drift over back to your regular scheduled thread.
 
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Ian

Notorious member
Here ya go, Rick, for a crude little plain-Jane Springfield M1A, if you have a 311041 mould and some WW+2% tin, air cooled, and somewhere around 36 grains of IMR 4320, military brass, Felix lube, and some CCI 200 primers you too can be happy:



That's a hunnert yards, and the pastie is 1". Not bad for some ancient cull bullets I was trying to get rid of so as to not waste the checks.

Joe, your assessment of Brinell numbers relating directly to "hardness" vs. toughness is more correct than what I indicated in post #2. What I was trying to do there is make the same important distinction between "hardness" and "toughness" that you did above. When considering alloy and state of anneal for a particular purpose, one must not only consider harness, but also malleability, and further ductility (different and sometimes mutually exclusive properties).
 

Rick

Moderator
Staff member
I don't have 311041, what does that bullet weigh? I've used 200, 180 gr, 165 gr and 150 gr bullets. Best yet is the RCBS 165 Silhouette bullet with 27 gr N-140. At 34 gr the 180 and 200 gr were terrible, dropped the bullet weight to 165 and the charge to 27.0 gr gets me about 2 inch groups at 100 yards (twice now). On the burn chart N-140 is right next to Varget and 4320 and is a short stick powder. Also I'm using #34 per BruceB's recommendation.
 

Ian

Notorious member
I think about 170 grains. The 311-679 works great, too, mine drops around 207 grains. I'll be trying a new one this weekend, around 160 grains. If this works out I'll cast more and send you some.
 

fiver

Well-Known Member
the rcbs boolit isn't gonna give you happiness much over the rpm thingy. [trust me I have tried, and tried, and tried]
seriously you need to match the throat a bit better..
 

Ian

Notorious member
the rcbs boolit isn't gonna give you happiness much over the rpm thingy. [trust me I have tried, and tried, and tried]
seriously you need to match the throat a bit better..

Yeah, exactly. The RCBS sil bullets are two, parallel diameters, no taper, like most of the Lee designs, getting one in a bore straight is like trying to set a beer can in a funnel straight, ain't gonna happen, wants to go wongo. Those designs are no good for pushing the velocity, and not great at the normal velocities post people shoot cast. My Lee group buy copy of the 311041 has a middle step on the nose that, though parallel, gives just enough intermediate support between nose and body to hold up to about 2200 fps. The 311-679 has a beautiful parabolic taper from nose to front band and it fits a lot of throats well. Bob's .30 Sil is a good one too. I had another design drawn up that I'll be testing this weekend hopefully and theoretically should be the cat's ass for most any .30-caliber throat. I'll letcha know how it goes.
 

fiver

Well-Known Member
it's pretty close.
Bob designed one for the swiss rifle based on the rcbs boolit, it however has that same tapered front drive band as his 30 cal boolit Ian and Brad use.

I have shot the rcbs silhouette boolit in my swiss rifles but I have to use ww and soft lead to get the nose dimensions just so, as the boolit relies heavily on that nose to align the base with the barrel and for a ton of support in the rifling.
I use 4/6/90 alloy for it now in several 30 cal rifles, and it will shoot groups as small as the rifle will shoot, only not at a velocity much over 1900 fps.
it seems to do it's best right below the edge of it's velocity ability [don't matter the powder used] if you get good engraving on that nose.
 

45 2.1

Active Member
Bob designed one for the swiss rifle based on the rcbs boolit, it however has that same tapered front drive band as his 30 cal boolit Ian and Brad use.

I'd like to know just which one you mean? The 30 Sil was designed for the 7.62 Natos and a Rem 700 in 30-06. The throat wear patterns were overlaid in CAD (that allows precise dimensions) and used for the nose dimensions. A lot of other throats in 30's were compared also, that is where the 30 Sil Heavy came from. Basically, once a throat washes some, it stays at the same configuration, but moves forward with wear.


I have shot the rcbs silhouette boolit in my swiss rifles but I have to use ww and soft lead to get the nose dimensions just so, as the boolit relies heavily on that nose to align the base with the barrel and for a ton of support in the rifling.
I use 4/6/90 alloy for it now in several 30 cal rifles, and it will shoot groups as small as the rifle will shoot, only not at a velocity much over 1900 fps.
it seems to do it's best right below the edge of it's velocity ability [don't matter the powder used] if you get good engraving on that nose.

Straight WW air cooled works best for the RCBS 165gr. Sil in the older Swiss rifles due to their tight barrel dimensions. The K11 is the best one for it. The velocity you state is about the max with faster powders due to it's lube capacity, which isn't enough to go past 2,200 fps well.
 

Rick

Moderator
Staff member
If memory serves me correctly the 30 silh came in 180 gr and 200 gr and both from Miha. If I'm correct that kinda leaves out the 200 gr because of the 2 year wait to get one. I don't have the 180 gr either but do have access to borrow one.

So is the MP 200 gr or 180 gr a good choice in the M1A? Has anyone here used either of these bullets in the M1A? I probably have 12-15 30 cal molds but reading BruceB's results on the M1A I have none of the bullets he used. Anyone ever stop to consider how many 30 cal molds there are? Hundreds of them.
 

Rick

Moderator
Staff member
I have access to a MP 180 Silhouette mold, I'll get that and try it out. From what I'm gathering from this thread the major difference is in the nose shape and how it fits the throat.
 

Winelover

North Central Arkansas
I shoot both in my M1A and I have a load for that 200 grain that would make most mouths water for a great deer load. I almost shoot the 180 exclusively in my AR10 and M1A. Also if I had a decent scope mount system of my old Model 81 Remington semi auto rifle I'd have all of you calling me a liar as how good that old bugger shoots the 180 Sil. My old eyes aren't any good for iron sights anymore, but like I told Ian once there are certain rifles with certain sights that I can shoot fairly well and two of them are that old Model 81 Remington and the M1A with it's National Match sights. So with handicap eyes I've shot 1 inch groups at 100 meters with the Model 81. I'm not D&T'ing the collectable rifle to see how it really shoots.

If I'm not mistaking that we're talking about the same bullet moulds, the 200 grain is the 06 bullet with three crimping grooves so it is a little bit different because of those crimp grooves.

What powders are you using with your AR and the 180 SIL. I recently shot a 5 shot, 3/4" MOA @100 yards with air cooled alloy. Load was 27 grains of H-4895 and CCI 200 primer. Went right back to bench and loaded 10 more but I couldn't duplicate the group. That group was 2 MOA and a tad more to the right.:( I have also used AA4350 with(CCI 250) magnum primers but I can't get under 2 MOA. I have yet to try Varget.
 

fiver

Well-Known Member
Bob airc it was a group buy from about 8 years ago. [noe?] would have been about the time Al was getting going anyway.
I remember it because I had just started shooting the rcbs boolit in my swiss rifles and didn't think there was a better option.

i looked at the new design and was a little confused at the time because I didn't fully understand how the throat tapered into the barrel, nor the relationship between alloy and how it flowed under pressure.
funny how shooting cast that little bit faster [and actually measuring a rifles critical dimensions] changes ones perceptions on designs and possibility's.
 

Ian

Notorious member
My dos centavos, I don't have an AR-10 so this is just speculation based on similar behavior in other rifles: The other thing that could have changed is the gun...check for lead rings at the end of the chamber, and make sure the bases of the cases are coming out of the sizing die exactly like the ones that shot the good group. Just because you used the same sizing die doesn't mean the brass sprung back the same after being fired in an AR. The POI shift sounds like base sizing issues to me, or lead scrapings in the front of the chamber on one side. I never got H or IMR 4350 to shoot well with cast bullets in ANY .308, at any speed.

I'm going to start an M-14/M1A thread, looks like there are at least four of us on here that have them and shoot cast bullets in them, it could get interesting. You AR-10 guys chime in, too.
 

Winelover

North Central Arkansas
I'm using 867 surplus with a booster. I too have tried 4350, but it's not giving me the groups. My bullets are oven heat treated and they are HARD. They are made of slightly hardened up 50/50 alloy. I'm going to be testing some faster canister powders as soon as the weather breaks again, raining now. Try refining your 4895 load because if you got that 3/4 group once you can get it again, something changed reloading for it again.

Did you chronograph that 4895 load? It's not going very fast.

Did not chronograph.....the muzzle blast is so severe with my Armalite carbine that I only get Errors. PITA setting up blast shield. I have settled on oven heat treating, but I wanted to use up the small amount of air cooled boolits I have. The only thing that changed was the ambient temperature by 10 to 15 degrees. I loaded them about a hour later with temps rising on a abnormally warm day. I load 15 feet from my bench. Same batch of brass, primers, etc. I use a RCBS Chargemaster to dispense powder. Dies were the same setting, unchanged.

I'm not getting into duplex loadings. Surplus is as hard to find as canister and price discrepancy isn't what it once was.
 

Winelover

North Central Arkansas
My dos centavos, I don't have an AR-10 so this is just speculation based on similar behavior in other rifles: The other thing that could have changed is the gun...check for lead rings at the end of the chamber, and make sure the bases of the cases are coming out of the sizing die exactly like the ones that shot the good group. Just because you used the same sizing die doesn't mean the brass sprung back the same after being fired in an AR. The POI shift sounds like base sizing issues to me, or lead scrapings in the front of the chamber on one side. I never got H or IMR 4350 to shoot well with cast bullets in ANY .308, at any speed.

I'm going to start an M-14/M1A thread, looks like there are at least four of us on here that have them and shoot cast bullets in them, it could get interesting. You AR-10 guys chime in, too.

I broke the AR down and gave it a through cleaning the next day. No leading in barrel and no lead in chamber. A couple days before, while shooting the AA 4350 with standard primers, I was having chambering issues but turned out to be a combination of soot and powder residue. My bench has a white top and powder residue is readily apparent. After a quick cleaning, it chambered remaining rounds without a hiccup.

I, for one, would welcome a thread devoted to semi-auto rifles.
 

45 2.1

Active Member
Bob airc it was a group buy from about 8 years ago. [noe?] would have been about the time Al was getting going anyway.
I remember it because I had just started shooting the rcbs boolit in my swiss rifles and didn't think there was a better option.

i looked at the new design and was a little confused at the time because I didn't fully understand how the throat tapered into the barrel, nor the relationship between alloy and how it flowed under pressure.
funny how shooting cast that little bit faster [and actually measuring a rifles critical dimensions] changes ones perceptions on designs and possibility's.

We did a GB with Lee for the first 30 Sil design, but never with Noe. The RCBS 165gr. Sil fit the tight dimensioned Swiss throat and barrel well (with Unique at about 1,500 fps it's a tight shooter too), but ran out of lube before it exited when you got to higher velocities, the 30 Sil doesn't do that. People need to understand that shooting bullets at higher velocities requires you to change how you do things and how you think about fit of the bullet to the case neck and throat.
 

45 2.1

Active Member
I'm not getting into duplex loadings. Surplus is as hard to find as canister and price discrepancy isn't what it once was.

That's your call........... Surplus 50 cal. and 20mm powders gets you higher velocity with accuracy when done correctly at lower pressures when you don't get it conventionally with normal powders. I've went that route since getting an M1A in 1983 and have ran thru several different obsolete powders now. All depends on what you want. Right now GI Brass has surplus 860 powder for cheap though. I got in on the cheap surplus 867 when it was widely available and bought enough to last.
 

45 2.1

Active Member
If memory serves me correctly the 30 silh came in 180 gr and 200 gr and both from Miha. So is the MP 200 gr or 180 gr a good choice in the M1A? Has anyone here used either of these bullets in the M1A?

MiHec has produced the 180 gr. one, but the 212 gr. heavy version has yet to be done by him. On the other hand, BRP produced both versions and both have been tried in the semi-auto rifles. 180 is best for the 308/7.62 Nato and the 212 works quite well in the Garand. Both do well in the M1A and AR-10.
 

Ian

Notorious member
I broke the AR down and gave it a through cleaning the next day. No leading in barrel and no lead in chamber. A couple days before, while shooting the AA 4350 with standard primers, I was having chambering issues but turned out to be a combination of soot and powder residue. My bench has a white top and powder residue is readily apparent. After a quick cleaning, it chambered remaining rounds without a hiccup.

I, for one, would welcome a thread devoted to semi-auto rifles.

Measure the roundness of your brass, both after firing in that rifle and after resizing, about 3/8" forward of the extractor groove. Compare to some resized brass NOT fired in that rifle.

I started a thread on the M14 style rifles, if you'd like go ahead and start one on AR-308s. I put it in the testing/shooting section.