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Confused New Member
Posted: Thu Jul 02, 2026 9:09 am
by Maxie10517
Hi everyone, hope there is someone out there that can help.
I have been trying to work up a load for my Golden Boy 45/70.
Nothing harsh for big game just a nice range load for shooting all day if I wish.
My choice of powder is IMR 3031, because I have tons of it and understand it is ideal for 45/70
Primer CCI LR Tried standard and Magnum.
Bullet is Hornady 300 JHP grain.
Bullets are factory crimped and not crimped.
I have several brands of brass, tried them all.
Powder charge right now is 42.0 grains all measured with a Balance beam and RWS Chargemaster scale used both to double check for errors.
All shots are Choreographed with Garmin Chron.
My problem is nothing is consistent. Some shots vary as much as 150 ft/s. Speeds from 1150 to 1350 f/s.
I have tried every Bullet from 300 grain to 405 cast but when Chrono. still nothing is consistent.
When I do get 5 consistent shots my groups go to 1 in at 100 yards.
Ready to toss the rifle and buy a Marlin.
Re: Confused New Member
Posted: Thu Jul 02, 2026 9:30 am
by DsGrouse
First, welcome to the forum.
So the first shot from a lever gun can be as much as 100 to 130 fps slower. Why? Cold bore and crazy freebore. It's just my anecdotal evidence across, 357mag, 44mag, two 45 Colts, 30-30, 375 Win, and 45-70.
If you are shooting for groups, discount the first one if it is wildly out of velocity spec. If you are shooting for hunting groups. Give the gun 5 minutes to cool down between each shot. That will even out the cold bore velocities.
Second, give a crimp. Those rounds are changing depth under recoil. The second I crimped any of my lever gun loads, the SD and spread narrowed by considerable levels.
I just spent weeks working up loads for my 45-70 using IMR 3031, for subsonic with 400grains I am using 32 grains of IMR 3031 seated to a case length of 2.600, out of my guide gun that runs 1070 in 90-degree weather. If you are loading subs, remember to work backward. Start with a larger powder drop, and remove powder until you get to the desired velocity.
For Campro 300 dual plate bullets I run 48 grains of IMR 3031 at a coal 2.6075, out of my guide gun that runs 1600fps.
For hornaday 300grain bullets, I'm at 47.6 grains of IMR 3031 case overall length of 2.6075 for a 1625fps.
Make sure all the brass is trimmed to the same length. I received two hundred new Starline pieces of brass, and they were all over the place. I trimmed them all down to min, chamfered and deburred them before loading them. Run a decent crimp, nothing beastly, but enough to stop setback.
I like 3031, as it allows me to have decent subsonic powder loads and great super loads with one powder.
Re: Confused New Member
Posted: Thu Jul 02, 2026 10:00 am
by Hatchdog
Welcome to the site. You have the right guy providing advice.
Re: Confused New Member
Posted: Thu Jul 02, 2026 10:02 am
by DsGrouse
larf. Don't let them kid you, my start date here is about 2 days after I started learning to reload.
Re: Confused New Member
Posted: Thu Jul 02, 2026 10:05 am
by HenryFan
Welcome to the forum. Glad you found us.
Re: Confused New Member
Posted: Thu Jul 02, 2026 11:26 am
by Maxie10517
Been crimping all my loads recently with Lee factory crimper. I feed rounds one at a time and seat all bullets to cant lure ring.
All brass is checked for size and over all length. At times first round is dead on as are 2nd and 3rd. than 4will go wild. Crono. reads high or Low.
I will see if pausing longer periods between shots makes a diff.
Like I said I'm confused. This is only caliber I cannot master or even come close. I am not new to reloading and think I know what I'm doing. Been reloading since 1964.
Any ideas are appreciated I will try anything if it sounds possible. Please help.
Re: Confused New Member
Posted: Thu Jul 02, 2026 11:34 am
by Maxie10517
DsGrouse wrote: ↑Thu Jul 02, 2026 9:30 am
First, welcome to the forum.
So the first shot from a lever gun can be as much as 100 to 130 fps slower. Why? Cold bore and crazy freebore. It's just my anecdotal evidence across, 357mag, 44mag, two 45 Colts, 30-30, 375 Win, and 45-70.
If you are shooting for groups, discount the first one if it is wildly out of velocity spec. If you are shooting for hunting groups. Give the gun 5 minutes to cool down between each shot. That will even out the cold bore velocities.
Second, give a crimp. Those rounds are changing depth under recoil. The second I crimped any of my lever gun loads, the SD and spread narrowed by considerable levels.
I just spent weeks working up loads for my 45-70 using IMR 3031, for subsonic with 400grains I am using 32 grains of IMR 3031 seated to a case length of 2.600, out of my guide gun that runs 1070 in 90-degree weather. If you are loading subs, remember to work backward. Start with a larger powder drop, and remove powder until you get to the desired velocity.
For Campro 300 dual plate bullets I run 48 grains of IMR 3031 at a coal 2.6075, out of my guide gun that runs 1600fps.
For hornaday 300grain bullets, I'm at 47.6 grains of IMR 3031 case overall length of 2.6075 for a 1625fps.
Make sure all the brass is trimmed to the same length. I received two hundred new Starline pieces of brass, and they were all over the place. I trimmed them all down to min, chamfered and deburred them before loading them. Run a decent crimp, nothing beastly, but enough to stop setback.
I like 3031, as it allows me to have decent subsonic powder loads and great super loads with one powder.
You have given me a few Ideas to try. I will let you know how things go.
Re: Confused New Member
Posted: Thu Jul 02, 2026 12:10 pm
by DsGrouse
Maxie10517 wrote: ↑Thu Jul 02, 2026 11:26 am
Been crimping all my loads recently with Lee factory crimper. I feed rounds one at a time and seat all bullets to cant lure ring.
All brass is checked for size and over all length. At times first round is dead on as are 2nd and 3rd. than 4will go wild. Crono. reads high or Low.
I will see if pausing longer periods between shots makes a diff.
Like I said I'm confused. This is only caliber I cannot master or even come close. I am not new to reloading and think I know what I'm doing. Been reloading since 1964.
Any ideas are appreciated I will try anything if it sounds possible. Please help.
What tempreture are you shooting at. You mentioned mag primers and regular primers. Have you changed regular primer brands?
how old is your 3031?
Re: Confused New Member
Posted: Thu Jul 02, 2026 2:51 pm
by Maxie10517
I shoot every day except lately since it is very hot here in Penna. temps vary. I have done some shooting in Winter with same results.
I have used Remington, Winchester and CCI primers. CCI in Magnum.
My 3031 is roughly one year old though I do have some older.
Mag. primers seem to give me a more complete burn. I have noticed some unburned powder using standard primers.
I am thinking now of trying something like a Redding collet die if there is such a thing.
Seems if I can keep a consistent tension on the casing necks that would be a big help. Just not sure if anyone makes such a die.
Re: Confused New Member
Posted: Thu Jul 02, 2026 5:35 pm
by DsGrouse
I didn't think it was the primers, and it sounds like it wasn't. More consistent ignition with a mag primer is to be expected, even if only to a small extent.
I've had powder go bad due to humidity, and that caused some weird issues for me.
Was the 3031 stored outside the factory container during a bout of humidity?
Was the lid tight on the 3031?
Is there any discoloration?
I don't think the issue is powder-related, but knowing those answers will eliminate it as the cause.
I still suspect it is tension of the case on the bullet. Whether it is a crimp of bullets or if they are loosely seated. So, let's take a look at that.
How are you expanding the neck for lead bullets and plated bullets seating?
I use a 45 cal expander; I think it is from a 454C set. I am using a Hornaday 45-70 seating die that has the bullet straightener, as their cowboy dies do. For a crimp, I've got 3: the Lee factory, a Redding profile crimp, and my RCBS seating die without the seating stem.
I've tried all 3, but it's the RCBS seating die that I keep using. Adjusting it to the 300 and 405 grain bullets seems far easier
I don't think your issue is loose powder in the case. I'm loading 32 grains, 10 whole grains less, and achieving single-digit SDs. But if you want to check that.
Pick up a little wad of poly-fil from a fabric store. Ball a chunk of it up and put it on top of the powder before seating the bullet.
Re: Confused New Member
Posted: Thu Jul 02, 2026 7:33 pm
by Maxie10517
I have tried poly fill before, cannot put much in case since 3031 almost takes up all the space, but will try.
My expander die came with set it is a RCBS die set, I set it to take up roughly 1/4 in to start bullet in. Looking for more even grip and as much of case mouth to hold bullet. I also factory crimp with Lee factory crimp die.
All my powder is in original containers and stored in dry spare room. I also shoot a lot with my M14 or rather M1A and achieve excellent groups with the same MRI 3031 powder.
If I could get something near what you are getting I would be super happy. 100 f/s and sometimes 150 f/s SD is not near what I expect. Like I have said I am not new to the game but this cartridge is driving me crazy. Never in my life have I run into a problem like this.
I am going to try a Lee collet neck expander to see if a more uniform consistency will help. Going back to my M1A for awhile until die gets here.
Lets keep in touch.
Re: Confused New Member
Posted: Thu Jul 02, 2026 8:31 pm
by DsGrouse
Yeah, you've covered all the bases I can think of. I checked my expander plug, rcbs 45 cal expander plug
Left: Completed Case with crimp; middle: expanded case with bullet prepped; right: expanded case.
How much crimp I put on mine.
Expanded case, with bullet put in the case.
Expanded case
I suppose the last thing. Have you slugged the bore? Or do you have pin gauges that you can use to check the bore?
When I started with 45 colt I was over-flaring the case. When I seated the bullet, I would have to run the bullet to lee's factory crimp die. When I did that, it pretty much undersized the bullets. I was having a heck of a time with accuracy. As soon as I backed off the flare it needed less correction in the crimp die. That helped the loads considerably.
If the crimp doesn't help even things out, slug the bore, check the jump from the bullet to the lands. I load my gun to about 0.015 off the max distance the lifters will feed into the gun. That helped quite a bit, also. I wonder if your rifle has an excessive jump to the lands and grooves.
In that same train of thought, how is the obturation of the cases? any black sooty spots on cases?
Re: Confused New Member
Posted: Fri Jul 03, 2026 9:28 am
by Maxie10517
Yes I do get some soot on cases. I didn't think of slugging the bore but will try. I am around .020 off lands and grooves.
Thanks again for all the help you have given me a good starting point.
I will let you know how things work out.
Re: Confused New Member
Posted: Fri Jul 03, 2026 11:29 am
by DsGrouse
I hope we figure it out. It has me and my limited knowledge stumped.
Re: Confused New Member
Posted: Fri Jul 03, 2026 11:49 am
by Mags
Soot tends to occur more with the larger calibers including 45-70. Presence of soot usually means there isn't enough pressure built up to force the brass to expand and fully seal the chamber. A heavy tighter crimp and fuller powder load should help (42gr is pretty light. Try 54 to 57gr). Even though you have a lot of 3031, also switching to a faster burning powder should help minimize soot.
Re: Confused New Member
Posted: Fri Jul 03, 2026 2:54 pm
by Maxie10517
Don't get a lot of soot and not on all cases. This is leading me more to believe it's neck tension. I will feel better if I can get a consistent neck tension on the bullets and know it is the same round after round. I will see when I try the Lee Lock Collet Neck sixing Die I have on order.
Don't want to go much higher on my loads mostly looking for comfort. I understand the old Trap Doors using black powder ran around 1300 f/s. This would be an ideal speed for me.
Thanks again for you time guy's I will let you know how things work out.