Starting Load Needed

Discussion of BPCR loading techniques, SAFETY, Case Cleaning and Prep, Indexing, BP Choice, Primers, Wads, Compression, Drop Tubes, Vibration, Load Testing, etc.
Dan97526
PostsCOLON 13
JoinedCOLON Sat Nov 24, 2007 5:35 pm

Starting Load Needed

Post by Dan97526 » Wed Oct 21, 2020 12:17 am

I just got my rifle, and there's an NRA BPCR Silhouette match this coming Sunday, last one for the year at my local range. I have time to sight in but that's about it. I have a lot of experience loading smokeless bottleneck rounds but black powder is new territory. I am well aware that what works in your rifle may not work in mine. I have all needed reloading equipment, including a compression die.

That said, I need a load (actuslly just a charge weight) to give me a starting point to shoot this weekend. It needs to get me to 500 with a decent trajectory and deliver enough energy to knock down rams. I'm not expecting an optimal load but as i said, i really want to shoot this match and i have no time for load development. Thanks in advance.

The following is what i have to work with:

Winchester BPCR, 45-70, 30" barrel, 1-in-18" twist
Starline brass
Old Eynsford 1.5F or 2F, i have both
LP, LR, and LRM primers
Lyman 457125, 20-1, lubed with SPG, 513gr as cast
0.030 poly wads

semtav
PostsCOLON 242
JoinedCOLON Sun Sep 27, 2009 3:07 pm

Re: Starting Load Needed

Post by semtav » Wed Oct 21, 2020 8:42 am

just make it simple
LR primer,
enough powder to need just a little compression to chamber the round if you have a compression die. or no compression if not
1 or 2 ldpe wads and be done.
wont matter if you slip fit the bullets in as fired brass, or if you have them sized.
Object is simply to get them loaded so they fit in the rifle.
Then just have fun

Dan97526
PostsCOLON 13
JoinedCOLON Sat Nov 24, 2007 5:35 pm

Re: Starting Load Needed

Post by Dan97526 » Wed Oct 21, 2020 10:10 am

Thank you. The problem I'm having with a zero-compression load is that to bring the powder column + wad up to the base of the bullet requires 55.5gr (by weight) of 1.5F in the case (seating depth is 0.593", 0.005" off the lands). I'm seeing all kinds of information online with people getting zero-compression loads at 62gr+ in Starline cases, which is far off from my own experience. I went to 61.0gr and needed to compress approximately 0.230". One time the poly wad popped out after I compressed it. I'm using a 36", 0.5" diameter drop tube.

Based on the velocities people are reporting, I suspect my 55.5gr load would be in the 1000fps neighborhood.

semtav
PostsCOLON 242
JoinedCOLON Sun Sep 27, 2009 3:07 pm

Re: Starting Load Needed

Post by semtav » Wed Oct 21, 2020 5:48 pm

Yea, looking at that bullet, it probably is seated deep. Sounds like the 61gr you came up with should be fine.
Are you compressing with or without the wad in place.
I've never had one pop out compressing with the wad in place but I have had the bullet pop back up when seating in unsized cases.
Just trapped air.
I like bullets touching the lands, but not saying yours is wrong.
I haven't shot that bullet in years but it should be fine at those ranges.

Most of the people getting 62 gr in are probably shooting as fired cases or bore riding bullets .
I just poured 60 gr in a PMC case (dont have a starline) and it was .350 down in the case.

semtav
PostsCOLON 242
JoinedCOLON Sun Sep 27, 2009 3:07 pm

Re: Starting Load Needed

Post by semtav » Fri Oct 30, 2020 7:25 am

Don't keep us in suspense, let us know how you did!!!

Dan97526
PostsCOLON 13
JoinedCOLON Sat Nov 24, 2007 5:35 pm

Re: Starting Load Needed

Post by Dan97526 » Fri Oct 30, 2020 11:25 am

It went well. I used a Lee dipper that got me around 58.5gr by weight of OE1.5, seated 0.005" INTO the lands (on your advice). Compression was minimal.

I didn't have a chance to chronograph it or do any work on paper, but I did have a 100yd zero and the velocity for a different load that I figured was pretty close. I think it shot pretty well. I started on pigs and used my known velocity and ballistic coefficient to get pretty close. I was on in 3-4 rounds. After that the drops for other yardages were close to what I calculated. We had shifting winds all day.

I started the day with the fine ball-and-post front sight insert, but with a center hold I was losing it against the also-black silhouettes. On the advice of another shooter, I went to the wide open crosshair and that worked a lot better. I didn't have a whole lot of success with turkeys (think I hit one in five rounds), but I did hit four straight rams after the insert change.

Chickens...well, no doubt you can guess how that went. I got dialed in from the bench. Went to offhand, and drilled the first one. Easy, right? I then proceeded to miss four straight.

All-in-all, I am extremely pleased with the rifle and the load seems to be good enough for now. Thanks for your advice!

For posterity, and in case I lose them, here are my vernier sight settings. I am a little surprised by the difference between 400 and 500. Coming from 300 to 400 is 19moa, but 400 to 500 is 15? I need to verify that. My ballistics software predicts 65moa at 400, and it's very close at other yardages. Maybe that's why I shot turkeys so poorly.

200 34moa
300 52moa
400 71moa
500 86moa

Plainbase
PostsCOLON 128
JoinedCOLON Thu Nov 24, 2005 11:26 am
LocationCOLON Out West

Re: Starting Load Needed

Post by Plainbase » Mon Nov 02, 2020 9:37 am

400 is not a standard distance for turkeys. If they are at the standard distance, your comeups are even odder.
Plainbase

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