BHuij
Active Member
Hey everyone--
TL;DR: Really terrible results with loads ranging from 37-40 grains of IMR 4895 in my 91/30. Using the Lee .312" 185gr RN with a gas check and Felix lube. Alloy is COWW heat treated and quenched to ~19 BHN. It's not just a bad rifle; I've had good results with other loads. Help me figure out why so I can fix it?
I got inspired to see what I can get out of my 91/30 beyond the standard mouse fart loads found in the Lyman Cast Bullet Handbook 4th Ed. I already worked up a pretty decent plinking load using the Lee .312 185gr RN mold and air cooled, powder coated COWW alloy, with an aluminum gas check. 23 grains of IMR 4227 got me reasonable accuracy out to 100 yards. Not anything special, but minute of steel plate at least.
However, I want to use this as a hunting rifle. I don't have a chrono, but a little math tells me my IMR 4227 load is somewhere in the neighborhood of 1750 FPS. That translates to roughly 1100-1200 foot pounds of force delivered to the target, depending on range. Probably enough to handle a deer, probably not enough to cleanly and humanely take anything much bigger.
So I decided to try for something hotter. After lots of reading and research, I figured I'd try using heat-treated/quenched COWW alloy aged for 2 weeks. It was in the oven for 1 hour at 425 degrees F, so according to the LASC chart that puts me at roughly 19 BHN. Ideally able to withstand a lot more chamber pressure without deforming compared to air-cooled.
Unfortunately I couldn't powder coat after heat hardening like that or else I would anneal the bullets and undo all my work. So I pan lubed with Felix. Which was messy and sucky, but it worked and filled the lube grooves.
I seated just deep enough to cover both lube grooves, and tried loads of 37, 38, 39, and 40 grains of IMR 4895. Once again, no chrono, but I can estimate velocity to be around 2140, 2190, 2250, and 2300 FPS respectively. Each group got 10 rounds, fired off sandbags at 50 yards, using open sights.
I barely made it onto the paper for 2 or 3 shots out of each 10, and the shots that did were all over the place. Honestly the best I can tell you was that it appeared to be shooting high as a general trend, but the groups were nonexistent, and the bullets were just going everywhere. I tried holding low, high, left, and right at varying distances from my desired POI, and almost nothing worked. I'm not a crack shot with a rifle by any means, but I'm not totally incompetent, and I'm 100% sure that this was the loads not working, not just me. I didn't even bother firing the 40-grain batch. I wasn't getting anywhere with the first three loads, and my shoulder had taken a beating already. As a side note I ordered a rubber butt pad online as soon as I got home
SO, I need your help to diagnose my issues here.
Here's what I believe I can rule out:
-Bad rifle, bad bore. I have seen this rifle do just fine with PPU FMJ factory loads at 100 yards. I ordered 60 rounds of it so I would have some brass to reload. I've also seen it do just fine with my IMR 4227 load. I'm not trying to hit sub-MOA, but <4 MOA at 100 yards would be great for HV by my estimation, and certainly "on paper at 50 yards" is not outside the grasp of this rifle.
-Poorly zeroed sights. There was no rhyme or reason to where these bullets were impacting. As I mentioned before I tried holding sights at center, left, right, low, and high. Once in a while a projectile would hit the target. It was never repeatable.
-Undersize bullets. My bore slugged out to .314" in the grooves using a fishing weight. Since I expanded the cavities in my mold, my bullets drop at .315" using COWW. I usually size after powder coating back down to .315" Since these weren't PC'd, I just left them as cast.
Here's my list of suspects. Hopefully you guys can suggest which are/aren't likely factors in my piss poor results - and which ones are the first ones I should fix.
-Poor bullet fit (from a more advanced perspective). I have not yet done a pound cast, but maybe the bullet is really poorly supported as it jumps the throat to engage the rifling, and this is causing it to deform excessively?
-Seating projectile too deep in case neck. I think there was a pretty hefty amount of bullet travel through the throat before the bullet started engraving in the rifling. That certainly wouldn't have helped anything. I just felt weird about leaving a lube groove exposed when it actually had lube in it.
-Alloy too weak. This goes hand in hand with poor bullet fit in the sense that perhaps mixing in some linotype would help the bullet weather the first few microseconds of launch better? I don't want too brittle of a bullet for this load if I can avoid it; want to keep the terminal ballistics really good for hunting purposes, and ideally that means the bullet stays reasonably ductile.
-Wrong powder? I kinda feel like I did my homework on this one, but I'm not opposed to trying something like 3031, 4064, or Varget if someone can convince me that IMR 4895 is a bad choice.
-Wrong primers. Forgot to mention that when I first started loading for this rifle I accidentally bought 1000 CCI 250 LR magnum primers instead of regular large rifle. I'm poor, so I'm still using them. Could the additional pressure be deforming my bullet?
I'm thinking for the next tests, I'll make the following adjustments:
-Shoot at 25 yards. Yes I'll feel like an idiot, but at least I'll have some semblance of an idea where my bullets are going. I can stretch further out when I get closer to a working load.
-Go back to powder coating. Turns out you can heat treat after powder coating. I already have some PC'd 30 cal bullets that I heat treated/quenched to a target hardness of ~20 BHN. They'll be ready to shoot in about a week. Even if the Felix lube was working (and I'm not convinced it was at these velocities), doing lube by hand or in a pan sucks.
-Start a bit lower and work my way up.
-Seat out to the lands again.
Any insight or suggestions are appreciated.
TL;DR: Really terrible results with loads ranging from 37-40 grains of IMR 4895 in my 91/30. Using the Lee .312" 185gr RN with a gas check and Felix lube. Alloy is COWW heat treated and quenched to ~19 BHN. It's not just a bad rifle; I've had good results with other loads. Help me figure out why so I can fix it?
I got inspired to see what I can get out of my 91/30 beyond the standard mouse fart loads found in the Lyman Cast Bullet Handbook 4th Ed. I already worked up a pretty decent plinking load using the Lee .312 185gr RN mold and air cooled, powder coated COWW alloy, with an aluminum gas check. 23 grains of IMR 4227 got me reasonable accuracy out to 100 yards. Not anything special, but minute of steel plate at least.
However, I want to use this as a hunting rifle. I don't have a chrono, but a little math tells me my IMR 4227 load is somewhere in the neighborhood of 1750 FPS. That translates to roughly 1100-1200 foot pounds of force delivered to the target, depending on range. Probably enough to handle a deer, probably not enough to cleanly and humanely take anything much bigger.
So I decided to try for something hotter. After lots of reading and research, I figured I'd try using heat-treated/quenched COWW alloy aged for 2 weeks. It was in the oven for 1 hour at 425 degrees F, so according to the LASC chart that puts me at roughly 19 BHN. Ideally able to withstand a lot more chamber pressure without deforming compared to air-cooled.
Unfortunately I couldn't powder coat after heat hardening like that or else I would anneal the bullets and undo all my work. So I pan lubed with Felix. Which was messy and sucky, but it worked and filled the lube grooves.
I seated just deep enough to cover both lube grooves, and tried loads of 37, 38, 39, and 40 grains of IMR 4895. Once again, no chrono, but I can estimate velocity to be around 2140, 2190, 2250, and 2300 FPS respectively. Each group got 10 rounds, fired off sandbags at 50 yards, using open sights.
I barely made it onto the paper for 2 or 3 shots out of each 10, and the shots that did were all over the place. Honestly the best I can tell you was that it appeared to be shooting high as a general trend, but the groups were nonexistent, and the bullets were just going everywhere. I tried holding low, high, left, and right at varying distances from my desired POI, and almost nothing worked. I'm not a crack shot with a rifle by any means, but I'm not totally incompetent, and I'm 100% sure that this was the loads not working, not just me. I didn't even bother firing the 40-grain batch. I wasn't getting anywhere with the first three loads, and my shoulder had taken a beating already. As a side note I ordered a rubber butt pad online as soon as I got home
SO, I need your help to diagnose my issues here.
Here's what I believe I can rule out:
-Bad rifle, bad bore. I have seen this rifle do just fine with PPU FMJ factory loads at 100 yards. I ordered 60 rounds of it so I would have some brass to reload. I've also seen it do just fine with my IMR 4227 load. I'm not trying to hit sub-MOA, but <4 MOA at 100 yards would be great for HV by my estimation, and certainly "on paper at 50 yards" is not outside the grasp of this rifle.
-Poorly zeroed sights. There was no rhyme or reason to where these bullets were impacting. As I mentioned before I tried holding sights at center, left, right, low, and high. Once in a while a projectile would hit the target. It was never repeatable.
-Undersize bullets. My bore slugged out to .314" in the grooves using a fishing weight. Since I expanded the cavities in my mold, my bullets drop at .315" using COWW. I usually size after powder coating back down to .315" Since these weren't PC'd, I just left them as cast.
Here's my list of suspects. Hopefully you guys can suggest which are/aren't likely factors in my piss poor results - and which ones are the first ones I should fix.
-Poor bullet fit (from a more advanced perspective). I have not yet done a pound cast, but maybe the bullet is really poorly supported as it jumps the throat to engage the rifling, and this is causing it to deform excessively?
-Seating projectile too deep in case neck. I think there was a pretty hefty amount of bullet travel through the throat before the bullet started engraving in the rifling. That certainly wouldn't have helped anything. I just felt weird about leaving a lube groove exposed when it actually had lube in it.
-Alloy too weak. This goes hand in hand with poor bullet fit in the sense that perhaps mixing in some linotype would help the bullet weather the first few microseconds of launch better? I don't want too brittle of a bullet for this load if I can avoid it; want to keep the terminal ballistics really good for hunting purposes, and ideally that means the bullet stays reasonably ductile.
-Wrong powder? I kinda feel like I did my homework on this one, but I'm not opposed to trying something like 3031, 4064, or Varget if someone can convince me that IMR 4895 is a bad choice.
-Wrong primers. Forgot to mention that when I first started loading for this rifle I accidentally bought 1000 CCI 250 LR magnum primers instead of regular large rifle. I'm poor, so I'm still using them. Could the additional pressure be deforming my bullet?
I'm thinking for the next tests, I'll make the following adjustments:
-Shoot at 25 yards. Yes I'll feel like an idiot, but at least I'll have some semblance of an idea where my bullets are going. I can stretch further out when I get closer to a working load.
-Go back to powder coating. Turns out you can heat treat after powder coating. I already have some PC'd 30 cal bullets that I heat treated/quenched to a target hardness of ~20 BHN. They'll be ready to shoot in about a week. Even if the Felix lube was working (and I'm not convinced it was at these velocities), doing lube by hand or in a pan sucks.
-Start a bit lower and work my way up.
-Seat out to the lands again.
Any insight or suggestions are appreciated.
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