using jacketed powder charge for cast

[atr]

A quick question:
Is it possible / safe use a load for a jacketed bullet when using a cast boolit of the same weight?
thanks
atr

[RickinTN]

It is as the cast bullet will result in lower pressure than a jacketed bullet. Just be careful your charge doesn't result in more pressure than the cast bullet can withstand. Staring jacketed bullet loads may be a good place to start or may produce too much pressure.
Good Luck,
Rick

[schutzen-jager]

fwiw
the original Lee manual made no distinction between cast or jacketed bullet i am still using some of their recipes with no problem -

[Froogal]

When I can't find a recipe for cast bullets using the powders available to me, but the powder I have does have a recipe for jacketed bullets, then I just use that recipe for cast. Never had an issue.

[Harter66]

It works well with the "full case" slow for cartridge bottom lines powders . 4350 in 30-30 and 32 Rem are very good .

[Frosty Boolit]

I use the data interchangeably for cast or jacketed of the same weight but I pay close attention to how far the bullet is seated into the case. Especially when nearing maximum loads.

[stubshaft]

Yes, I've been doing it for many years.

[Beerd]

what Frosty said, watch your overall length.
..

[redhawk0]

I do it for the 30-30. 170gr Jacketed and 173gr Cast/PC'd....with the same load of powder gives me same POI at the target. I can't say this will be true for every cast bullet caliber...but this has been my experience. It's so easy to switch between the two this way.

redhawk

[atr]

thanks guys
best
atr

[Jtarm]

Generally speaking, it’s probably fine.

A couple things I’d keep in mind:
Jacketed bullets are groove diameter while cast tend to be a bit larger. The cast bullets could obturate to an even larger diameter.

Make sure they’re a fit to your chamber throat(s) and work up.

[JoeJames]

May be obvious, but the reverse when using cast bullet load information with jacketed bullets can be much more of a problem; especially with light cast bullet loads. It generally takes more pop to get a jacketed bullet out the barrel than a cast bullet.

[rintinglen]

As long as the amount of bullet in the case is roughly the same, the only slight danger is at very top end, max loads. Rule of thumb is that you'll be ok using J data for lead in pistols and revolvers, not so much in rifles. However, in cartridges that exceed 1400-1500 fps, severe leading can be a problem. For this reason, you will often see lower max loads for lead boolits than Jacketed ones.

[atr]

got it all,,,,basically I want to use this for revolver loads
atr

[sixshot]

Especially with revolvers the seating depth can make a big difference even if the bullets weigh the same. If the cast bullet is taking up more case capacity then you need to start your powder charge lower & work up because pressures are going to be higher. This is very important is small cases like the 9mm, etc.

Dick

[Outer Rondacker]

wait there's a difference lol

[243winxb]

Study this comparson , lead vs jacketed. https://www.thehighroad.org/index.php?media/albums/load-data-lead-vs-jacketed-bullets.265/

https://www.thehighroad.org/index.php?media/357-magnum.2913/full More at link.

https://www.thehighroad.org/index.php?media/357-magnum-lead-vs-jacketed-hodgdon-data-2020.2922/full

[GregLaROCHE]

I use it for rifle loads when I can’t find loads for lead boolits with the powders available here.

[gwpercle]

Since I have data for cast boolits and data for jacketed boolits ... I tend to use the appropriate data for the boolit I'm going to load .

It's not hard to get the correct loading data for the type of boolit loaded ... why not use it !

It reminds me of some things my Daddy used to tell me ...
" If you gonna do something ... Do It Right ! " and the other thing he used alot ...
" Boy ... Don't be acting the fool ! "

Gary
If anyone needs cast boolit load data ...just ask , you in the right place !

[Larry Gibson]

It is as the cast bullet will result in lower pressure than a jacketed bullet. ...........Rick

I did a fairly extensive pressure measurement test of numerous cartridges, both handgun and rifle, trying to prove that theory. I could not. Sometimes the cast bullet would give a lower pressure and sometimes it gave a higher pressure. Sometimes those higher pressures with top end loads could be called "excessive' or "unsafe".

"the cast bullet will result in lower pressure than a jacketed bullet" is a myth.

[justindad]

I have non-destructively over-pressured a few rounds following the myth that jacketed data applies to cast. I believe some powders are higher risk than others. Look at the max charges for 158 grain cast and jacketed bullets in the Western Powders manual (image below) - jacketed can use significantly higher max charges, or not. For AA#9, the starting charge for Hornady 158g XTP is the max charge for the 158 grain lead SWC. Case capacity and OAL do not fully explain this discrepancy. For AA#7, cast and jacketed 180g have the same max charge.
*
Lyman’s 49th manual (not shown here) even shows various cast bullets of similar weights can have significantly different charges… but only for certain powders.
*
I hypothesize that lube grooves & cannelures affect the torsional stiffness of a bullet, which may cause increased drag in the barrel (and therefore lower velocities at similar/higher pressures). I also hypothesize that a powder’s burn rate is dependent on the pressure, and that this dependency is stronger & weaker for different powders. If the relationship between burn rate and pressure is relatively weak, then you can more safely use jacketed data for cast. If the relationship is strong, then all bets are off. I gage how strong this relationship is by collecting load data for a bullet weight & powder from multiple sources and reviewing the range in max charge levels - big range = big risk.
*
312679

[atr]

interesting reading guys, I am glad I asked the question
thanks
atr