Velocity w/ cast vs. jacketed

[n5odj]

I sure hope I'm not becoming a pest. Just so many questions & there's some great experience here.

If I load my 45/70 rounds w/ the same powder & charge as I did while using jacketed bullets, how will cast bullets compare in velocity - as a general rule? This assumes that the bullet weight is the same & the powder & charge are the same. Also, all would be well within safe loading parameters.

Thank you,

Robert

[9.3X62AL]

WAY TOO MANY variables in the internal ballistic equation to give a simple, one-size-fits-all answer to your question. The general rule is that cast boolits vs. jacketed bullets in this scenario produce less pressure, less friction, and less bore drag than their jacketed counterparts--which COULD result in elevated velocities. Of course, then you get into powder behavior's interface with the time/pressure curve, as influenced by bullet diameter, metallurgy, shape factors........I'm already getting a headache.

I hate to answer questions with questions.

NO, you are ABSOLUTELY NOT a "pest". I'm sure others will chime in with their viewpoints on this issue, and I damn sure don't hold the patent on The Ultimate Truth To Cast Boolit Questions. Not by a damn sight.

Wait until others join in, and weigh all the responses in light of your conditions and experiences.

[David R]

I think they will work, but............. You should start low and work up or you may be discouraged.

I would start with a few powders and start low. You will find one that the gun likes and go up from there unitl it works or falls apart.

My 308 shoots 20 grains of 2400 GREAT, but 25 is useless. I am going to try some slower powders to see if I can get the velocity up a little more. It seems to have an OFF switch at 2,000 Fps.

Try this and that from the lyman manual if you have it. You will get to know your gun better.

To answer your question, the velocity will be close. Who knows about accuracy.

Naw your not a pest. Ask away

[n5odj]

BTW, I generally keep my velocities low/midrange in this guide gun. I've never been a speed freak when shooting the 405grn bullets. I keep it around 1400 fps, which is PLENTY for deer & paper & it pretty much matches factory load velocity.

Robert

[MOA Shooter]

I sure hope I'm not becoming a pest. Just so many questions & there's some great experience here.

If I load my 45/70 rounds w/ the same powder & charge as I did while using jacketed bullets, how will cast bullets compare in velocity - as a general rule? This assumes that the bullet weight is the same & the powder & charge are the same. Also, all would be well within safe loading parameters.

Thank you,

Robert

Robert your question is a great one IMO. As mentioned the variables are so long a laundry list a definitive answer isn't readily available. May I suggest researching the problem with your own gun and posting the results. This would be interesting to the many reading along here and I promise you the doing would be very enjoyable.

MOA.

[The Nyack Kid]

some of the slower powders that work good with jacketed boolets in the 45-70 , AA 2495 comes to mind , dont work very good with cast . a case filling load of AA 2495 with a cast 460 gr aircooled WW boolet does not burn completly leaving a mess every were . there is not enough resistance with cast hence lower pressures and unburned powder hence lower velocities. in fact with 45 grs of AA 2495 and a 315 gr cast , i had a boolit get stuck in the bore , not fun but not a lot of recoil either. like Deputy Al said "too many variables" for an absolute answer . give us a couple of load combos to work with and we might be able to say , yay or nay ( im a poet !)

[n5odj]

Alright, here's the jacketed load:

46grns IMR3031 w/ Rem Soft point 405grn. Average velocity 1390 fps.
48 grns averages 1415 fps.

I've got some rounds loaded w/ the cast bullets using the above loads & will definately report back with the chronograph results, although it'll likely be a couple of weeks before I can get to the range.

Sure appreciate ya'll's input & help.

Robert

[The Nyack Kid]

Really ??? thats 46 grs 3031 with a rem 405 mmm whats your barrel length ?I have a ...... had alot of 30 year old Imr 3031 that i worked up some loads with a japchester 1886 extra light 45-70 . i was going though my notes and with 50 grs of Imr 3031 and with a 400 gr speer i got 1725 fps . I have a 460 gr Mountain mold that likes 47 grs of imr 3031 these boolits move along at 1710fps . NEI that weighs 485 gr , 45 grs 3031 @ 1630 . tried a Cast Proformance 420 gr with 52 grs 3031 got 1880 fps and a heck of a bruse . hope this helps .

[BruceB]

Robert, sir;

Definitely, there is NO "pest factor" in your questions, or even on this Board, near as I can tell. If there's a question, just ask....that goes for oldtimers and greenhorns and everyone in between. Questions OFTEN give rise to excellent discussions, which not only educate the questioner, but also refresh memories and actually lead us into new fields.

I agree with Deputy Al and his statement about the variables. Try what seems reasonable, and adjust according to results.

I had occasion in the last few days to refer to the three editions of the Lyman Cast Bullet Handbook in my possession.....'53, '67, and 1980 or thereabouts, without going out to check???

Anyway, even the latest one is woefully inadequate in the loading tables. In many, many rifle cartridges, the Lyman loads never use anything slower-burning than maybe (obsolete) WW-630. I'm beginning to question the wisdom of sending off new casters to find that book. I'll grant that the technique and procedures section is pretty good, but I think in future I'll recommend that newbies be very cautious about using those fast-burners which Lyman used so much. 700X in the .460 Weatherby Magnum????? I don't THINK so!!! We here use a LOT of medium-to-slowburners in our loads, but there's nary a hint of this well-proven utility in the Lyman manual. The casting world needs some good NEW references.

N5odj is on pretty firm ground, starting out with 3031, although in his .45-70 I might be inclined to go with something a bit faster-burning, like 4198 or even 2400 for openers. I'm kinda new to the cartridge myself, and I'm still exploring the possibilities. I doubt that my Shiloh's new barrel will EVER see a jacketed bullet....it just isn't done, old boy, eh wot? Robert, I'd recommend that you not get too concerned about duplicating your jacketed velocities right off the bat. I'd drop the speed a bit for the first while, and just play with charges and powders until you get familiar with what your rifle prefers.

Welcome; you are among friends here.

[buck1]

Unless your bullet is dead soft I dont see any problems with it. The pressures related to that seem to be low. I wouldnt be spooked of it. FWIW..Buck

[Buckshot]

..............Dealing in simplicities here, and Deputy Al was beating around the bush with it, is that the cast lead boolit SHOULD be faster then the FLGC one. Lead is basicly a dead metal without a whole bunch of springback. Meaning once it's engraved it doesn't expend much effort pushing back. Add to that that the engraving process itself is much easier, you'd think that 'faster' fact would be the answer.

All you can do is to go out and see.

I seem to remember a HUGE flame war getting started at Shooters.com on the reloading board about his very question (or maybe it was to do with pressure?). One VERY vocal individual said that it was a well known fact that lead was easy to upset and by this very function pressed harder against the barrel walls, so was more likely to be slower and/or build dangerous pressures.

I should have printed that one off as it got pretty steamy.

..............Buckshot

[n5odj]

Nyack, The gun is a Marlin GG, so the barrel is 18.5" long. I did notice (which I've read here & elsewhere) that 3031 does better, with more consistent velocities w/ the higher charges. Yep, there was some unburnt powder too, but again, the higher I went, the less that occurred.
BruceB, I actually started (w/ the jacketed bullets) using 4064 since that's what I had & that's even slower than 3031. That worked quite well w/ good speed & accuracy.

Oh, life is so tough..... Now I just have to get to the range to play with the loads. :-)

I guess the upshot of all this is that I was trying to minimize the startup time to work up a load for these cast bullets. My range time is, unfortunately, limited right now & deer season is coming up in November.

Robert

[BABore]

Prior to getting into casting my own, I was shooting a lot of Cast Performance and Jae Bok Youngs hardcast in my 450 Marlin Guide Gun. I have always used H322 powder for my jacketed and cast loads. I've used 420, 460, and 550 grain bullets sucessfully with this powder. Velocities were 1,500 fps for the 550's to 1,800 fps for the 420's. All of these bullets were gas checked. Before I frequented here, I got a lot of info from the Marlinowners forum. There's a lot of commercial cast shooters there, as well as a few casters. Most seem to use RL7, H4198, H322, and to a lesser extent H335 and 3031 powders. As soon as I get my gun back from the smith, I plan on trying some RL7 for my own lower velocity hardcast loads.

[Poygan]

I can't address the cast versus jacketed in a rifle but I experimented a few years back with a .357 6" bbl Rossi. Winchester cases, CCI std primers, start to max loads with 2400. 160 grain cast and 158 grain jacketed. 3 shot series.

11.3 grains: lead = 1172 fps
j = 1076 "

12.2 grains: lead = 1224 "
j = 1175 "

13.1 grains: lead = 1258 " (consistent: 1252, 1252, 1269)
j = 1209 "

14.0 grains: lead = 1320 "
j = 1270 "

14.9 grains: lead = 1423 "
j = 1333 " (consistent: 1323, 1340, 1335)

[felix]

Poygan, your results show what would be normally predicted assuming both types of slugs fit the system properly. It takes a certain amount of energy to begin the engraving of a slug, and that amount subtracts from any velocity production. Can we say 20-25K CUP is a demarcation threshold? Lower than that, the lead boolit will go faster in every case. Higher than that the terminal velocities approach equality. ... felix

[SharpsShooter]

N5odj,

My own experience with the 45-70 using cast bullets with jacketed load data was not exceptional. Unless the boolit is extremely hard or of gas check design, you will spend some time removing leading after a number of shots. I deveoped a reduced load with 405gr FN boolits using 4064 that consistently prints under 2" at 100yds in my 1895 Marlin. It runs at 1400fps and develops over 1700 ft lbs at the muzzle. Recoil is quite pleasant and it is a super Deer load. As a rule I don't try to run cast stuff into the high level velocities.

Regards

[44man]

I had a strange occurance with my 45-70 BFR revolver, can't answer why! I was shooting 300 gr Hornady's with 4198 and getting close to 1800 fps. Don't remember the load exactly but I think it was 47 grs. No pressure signs and the cases fell out when I tilted up the gun. I tried the same load behind my 317 gr hard cast GC boolit. I had to beat the brass out of the gun. I now use 31 grs. of 4759, dacron filler and get 1535 fps. Super accurate and does a job on deer.
This is the opposite of what happens in my other revolvers in that I am able to use heavy loads with even heavier boolits with no pressure signs. I have a hunch it was just my choice of powder for the cast boolit. I heard that 4198 can spike fast.

[n5odj]

I said I'd follow up when I got to the range, so here goes.

These cast bullets - 405grnMountain Mould FP w/ wide meplat (my very first castings ever) were loaded over 48grns IMR3031. I could only get a chronograph reading for eight shots since my chrono kept giving errors, but this sample of eight will have to do. Averaged 1565 fps.
The RemSP405 bullets averaged 1516. So there's my answer. I kept them all within a 6" circle at 100 yards using a ghost ring peep sight, which is as good as I could do w/ the jacketed bullets.

Just as an aside, the lube was 50/50 w/ one coat of liquid Alox on top of that. Absolutely no leading, but still getting a few unburned kernels of powder. No big deal since it shoots fine.

Robert in the hills of NC

[The Nyack Kid]

I didnt mention the lube that i use with my boolits .
It is slightly modified Felix lube . I added more perifin to the mix to harden it for summer time , it is still softer than green RCBS lube .

I beleave that a proper acting lube will help wring every last bit of performance out of a cast load . this is something to experiment with . [smilie=b:

still cant see how my 3.5 inch longer barrel would give me an extra 200fps with one grain less powder and a boolit that weighs 55grs more . well it is a older lot of powder for sure ... funny stuff no ?

[Buckshot]

.............Robert, thanks for posting the followup range report. It's nice to see the information. If you care too (you didn't mention using it) you might try a tuft of Dacron over the powder. Load up 5 like that and see what happens, velocity and accuracy wise. It would be a fine compliment to the previous one.

.............Buckshot