BPCR Exterior Ballistics

[DanTDesigns]

Just to get you 44-cal guys drooling, here's a CAD, wire-frame drawing and a 3-D rendering of the 44-cal "Money Bullet" for 17-twist barrels that I designed for SSShooter. Rick of KAL Moulds did the dirty work for us. Thanks Rick!!!

[.22-5-40]

Very interesting stuff! I have a question..I have an original Marlin Ballard A-1 Mid-Range .40-70, with bright perfect bore. The groove dia. is .4094" Bore dia. is .404" twist is 1-20" For shooting out to 500yds, what bullet nose style would you guys recommend? I cannot decide between the Ellipitical or the original Postell shape ? weight would be 330grs. as original loadings. These would be either g.g or p.p. I can chamber a .409 bullet seated in Betraim case. Powder would be Swiss 1 1/2 or 2FG. Thanks alot!

[bruce m]

dan,
does this mean that rick is now doing greasers?
keep safe,
bruce.

[DanTDesigns]

dan,
does this mean that rick is now doing greasers?
keep safe,
bruce.

Bruce,

I don't know if Rick is going to start making GG moulds.

[RMulhern]

dan,
does this mean that rick is now doing greasers?
keep safe,
bruce.

Bruce,

I don't know if Rick is going to start making GG moulds.

Rick told me the Pope would excommunicate him if he made greasers!!

[SSShooter]

dan,
does this mean that rick is now doing greasers?
keep safe,
bruce.

Bruce,

I don't know if Rick is going to start making GG moulds.

The answer I received from Rick this morning is that he will only be making molds for those who require penitence with their BP shooting (only PP).

[desert deuce]

Well......penitence with this group is a remote prospect.....confession on the other hand.....ain't gonna' happen

[bruce m]

it would appear that Mephistopheles has yet to enter the kal workshop.
keep safe,
bruce.

[DanTDesigns]

Dan, that bullet unfortunately is still just a touch long for when the wind comes up above 10mph. Shoots lights out at 1k until then tho..

Don,

I just reviewed your 1.35"-long, 44-cal bullet's stability. It has the same stability as Doc Lay's 45-cal Money Bullet that he's successfully competed with, in long-range matches for years. My take is that the reason your bullet doesn't buck the wind as well as you'd like is not because of instability. It is because the bullet is light for caliber when shooting from the 1,000-yd line. Your bullet's estimated BC is about 0.400. Doc's bullet's estimated BC is about 0.500. Those estimated BC's are averages over 1,000-yds.

[Don McDowell]

Dan, if the patched bullet I had Brooks make me at 1.29 inches long (455 grs) had not of out shot that bullet not once but three separate occasions in some screwy wind conditions at 1000 yds, I'ld say you're probably right,, but I'm going with the physical hard evidence.
By "outshot" that bullet I'll detail making the switch at Raton for you. Having shot your bullet at 800 with reasonable results, then having some trouble at 900, when we got to the 1000 dead calm conditions for 4 sighters, couple of x's and 10's, let's go for score. Immediately the wind came up and we're 4 shots into score with out a single point, nuthin , nadda, nyet, elzippo... I was laying there thinking about this train wreck about to happen, recalled I had a box of those 1.29 patched bullet (1370 fps at the Cooper Cabin) in my pickup. I jumped up and ran to the truck, (everybody thought I was quittin...or had gone nuts) came back with my patched rounds and in those last 6 rounds came back with a 40 something..
That 19 twist in the 44 barrel is a different beast to deal with.

[Don McDowell]

When I get thru playing with this 44-90 st and it's 16 1/2 inch twist as a midrange gun, I'll give those bullets of yours another run . I did load a few and shot thru this rifle at 600 and while they shot alright I did see a bit more verticle than I'm comfortable with, so need to get some proper load development going with those when I have other axes ground. I do think it's a pretty good bullet and when the wind isn't screwing with us, that thing just blows your mind how tight it shoot's at 1k in the 19 twist 44-77.

[DanTDesigns]

Dan, if the patched bullet I had Brooks make me at 1.29 inches long (455 grs) had not of out shot that bullet not once but three separate occasions in some screwy wind conditions at 1000 yds, I'ld say you're probably right,, but I'm going with the physical hard evidence.

Don, I'd like to see some holes punched through the target, by the 1.35"-long bullet, from the 1-K-line. Given my stability estimate for the bullet, when fired from your 19-twist barrel, I'm thinking the hole shape might add to our understanding of BPCR stability issues. If you get the chance, take some pictures of the bullet holes and post them here.

...recalled I had a box of those 1.29 patched bullet (1370 fps at the Cooper Cabin) in my pickup.

I'll do some BC and stability estimates for your PP bullet...be back in a flash. Ok, the BC is down at 0.350 and the stability factor is way up at 4.2. That is off the Richter Scale for a stability factor. Doc's 45-cal, winning bullet has a stability factor of 2.8, as does your 1.35" long bullet. Well, maybe we'll learn something if you can get some pics of the bullet holes produced by the 1.35"-long bullet from the 1-K-line. Heck, you could set up a corrugated cardboard target at your ranch and poke some holes though it. Your home range goes out to 800 or so yards, right? This is interesting. What did the ODG's shoot out of 19-twist, 44-cal barrels in Creedmoor matches? Maybe Orville can take a swing at that one. Ok, now my curiosity is getting the better of me so I'm going to do a wind deflection comparison between your two bullets...Back in a flash. So, here are the results from the 1-K-line when there is a 10 mph wind out of 9 o'clock. The PP bullet will deflect about 17 MOA. Your 1.35"long GG bullet will deflect about 14.7 MOA. The BC estimates assume the bullets are stable.

[Don McDowell]

Dan I will get back to those bullets and see what's going on, but the same basic thing happened at Byers the month before ,but there was also some problems with the scope mounts at Byers, so I couldn't totally discount bullet problems.
That's the neat thing about Eron's High Plains Challenge match, 3 strings of 10 at 1000 yds..
Yes I can shoot to 1 1/2 mile here at the house.. but it'll be a bit before I get back to messing with the 44-77 for long range work, but when I do, I'll be giving you a phone call..
I'm also wondering if maybe slowing those down a bit might not help as there could be a problem coming back down thru the transonic zone in winds..

[Don McDowell]

Oh, almost forgot, as to the bullets ODG's used in the 44-77 for Creedmoor shooting , Roberts said they were 480 gr bullets. The bullet that was given to me taken from an original factory loaded round is,, wait for it,,,, now don't guess.. 1.29 inches long weighs 458 grs....
I'ld really be interested to talk with Chip Mate, as he has certainly been making the 44-77 work and work quite well at long range.

[DanTDesigns]

...The bullet that was given to me taken from an original factory loaded round is,, wait for it,,,, now don't guess.. 1.29 inches long weighs 458 grs....

Was that a Creedmoor round? What twist-rate was that bullet used with? If it was a 19-twist, that is the most over-stabilized bullet that I've learned about that the ODG's shot, in Creedmoor matches. IIRC, the 45-cal, 550-gr, PP, Sharps LR bullet was shot out of a 19-twist barrel. My stability estimate for the bullet, out of a 19-twist barrel, is 2.4. That is significantly lower than the estimated stability of your 1.35"-long, 44-cal bullet. As a matter of fact, based on what I think I know about the ODG's loads, they were mostly marginally stable at best. I think we, in the modern era, have taken BPTR shooting a few steps up. Oh to have the best of the ODG's shooting against the likes of Doc, Gullo, DD, Eron, etc. Man, I'd pay to pull their targets.

I'ld really be interested to talk with Chip Mate, as he has certainly been making the 44-77 work and work quite well at long range.

Yes, that would be interesting.

Oh, damn, just thought of something else that might be causing problems. But, you'd have to send me a few bullet samples so I can assess the potential problem. Check your PM.