Need input on 30-30 load estimation

[KirkD]

I purchased a RCBS 30-180-FN mould for my 30-30, thinking it would drop a bullet around 180 grains. It turns out that if a fellow uses water quenched wheel weights, I'm getting a bullet that weights 200 grains (203 lubed and gas checked). Apparently, that is normal. So now I'm about to develop a load for a 200 grain cast bullet for my 30-30 carbine. Here's my thinking.

I want to keep the energy the same as for a 170 grain jacketed bullet.

28.5 grains of IMR 3031 under a 170 grain Hornady is supposed to give 2,000 fps.

Keeping the kinetic energy the same, I should be looking at 1,830 fps with a 200 grain cast bullet (actually, it might be faster, since a cast bullet will slide down the barrel easier than a jacketed bullet).

So, here's my plan. I'm going to start with 25 grains of IMR 3031 and chronograph the load, then slowly increase the powder until I get 1,830 to 1,850 fps.

My thinking is that kinetic energy is related to the energy inside the case, which is related to the pressure inside the case, so that is why I kept the kinetic energy the same for the heavier bullet.

Question: For those of you that use the RCBS 180 grain bullet, have you weighed your bullet and, for those who get a weight close to 200 grains, do you use IMR 3031 and, if so, what does your load chronograph at?

[w30wcf]

Kirk,
My RCBS 180 mold (circa 1980) drops bullets made from w.w. at 190 grs including the g.c.
Sounds like yours has a longer gc shank.

I have not used 3031 with bullets heavier than 170 grs so sorry I can't be of help there.

I do have a Old West Mold that drops a 205 gr. bullet. I use 35/H414 which is a capacity load and chronos
2,035 f.p.s. (24" barrel). Pressure runs a bit below 36,000 CUP (30-30 SAMMI MAP - 38,000 CUP) and it shoots very well.

w30wcf

[Leverdude]

I dunno if that makes sense to me Kirk if your compareing jacketed to cast. Not sure its a safe correlation in any event, but if a certain pressure creates a certain kinetic energy with a jacketed bullet, given that the kinetic energy is directly proportional to velocity and a jacketed bullet will need greater pressure to achieve the same velocity a cast bullet will I dont think you can make the presumption your making. I'd think you would need projectiles of similar construction to get meaningful data like that. If you go by 170 grain cast data I think your formula would be more acurate.
But I'd imagine that pressures would be less though so I guess its safe to try. Have you looked for any 200 grain cast data? Lees book has a boatload of cast data and likely has some.

[KirkD]

... I'd imagine that pressures would be less though so I guess its safe to try. Have you looked for any 200 grain cast data? Lees book has a boatload of cast data and likely has some.

Yes, the cast pressure will be lower so the actual velocity for the same energy in the case would be higher than 1,830 but I figured I'd stick with the conservative side of things. I have searched around for 200 grain load data and have not found any yet. None of my load publications here at home have published loads for a 200 grain bullet, and I've not been able to find any on the web. Ideally, I would like to use a slower powder than IMR 3031 but I just so happen to have a bunch of IMR 3031 so I'll use it.

w30wcf, thank you for that H414 load. That will be helpful information once I use up this IMR 3031 .... or I might just save the IMR 3031 for my 150 grain loads and get some H414 for my 200 grain loads.

[hartman]

Kirk,

Have a look at Juniors site the Frugal outdoorsman. He did some load development with that boolit years ago.

Hartman

[earlmck]

Kirk, August of '95 Handloader has an article by Ron Carmichael "Cast Bullets at Full Speed in the .30 WCF". He doesn't say what his RCBS 30180's weight but he does show different loads for them than for the Lyman 31141 (which I use and it weighs a tad over 180 grains for me). He shows 28 grains of 3031 giving 1985 fps with said 30180FN and notes it is his "second best load". (The best load was 30.5 gr. of AAC-2230 for 2055 fps). He used Remington brass and CCI 200 primers. Shot in Marlin 336C.

Oops -- he does say this weighs 195 grains. Missed that the first look through...

[KirkD]

Good info, gentlemen. Thanks. 195 grains is pretty close.

[Charles]

I have shot allot of 3031 behind 170-175 cast GC bullets. I have used 30 grains, but have dropped back to 29. I have had very good results with this load.

I see no problems with your plan to start at 25/3031 and going up. Were I you (which I am not), I would not worry about numbers, just find a load that shoots well in your rifle. No deer, or target will notice 100 fps more or less.

[KirkD]

Thanks, Charles, for that info. I'm pretty sure that 25 grains is very conservative. I'm thinking that I may wind up closer to 27 grains, we shall see.

[93marshooter]

Load book photo of page listing the cast bullet you mentioned.
I uses 26 or 29 gr. of RG4895 with the Lee cast 170 gr bullet with gas check. It works well but not at powerful as jacketed.

[KirkD]

That chart is very informative. Thanks for posting it. I'm surprised to see a MV of over 1,800 fps using 2400, a medium speed powder. The pressure on that one must impressive.

[Rimfire McNutjob]

I selected that RCBS mold in QuickLoad and bumped it's weight to 203 grains. With a 24" barrel and 25.5 grains of 3031, I get a peak pressure of 26,100psi and a velocity at the muzzle of 1843fps yielding 1532ft-lbs. The OAL was 2.55". That should be in the ballpark. To improve the estimate, I'd need the water capacity of a fired case and the bullet OAL. QuickLoad has the default case capacity at 44grains of water.

[KirkD]

Rimfire a big thank you for that info! Are you able to run the calculation with an input of 30,000 psi to get a 3031 powdr weight and a velocity?

[Rimfire McNutjob]

It looks like 26.8 grains of 3031 brings it to 30,250psi. This puts the muzzle velocity estimate at 1932fps. This load is just a smidge under 90% case capacity by volume.

To give you an example of how the case capacity can affect the estimate, I bumped the capacity to 45 grains of water from the 44 grains used by default for the .30 WCF case. That lowers the above load to 28,700psi and 1912fps from a 24" barrel.

You might want to verify that the bullet in question is 1.000" long as is show in QuickLoad. If it's longer, the data will change toward higher pressure and slightly higher velocity for the same loaded length of 2.550".

When you chrono these, remember I'm using MV. You'd have to knock off a little if your chronograph is 10ft or so away.

BTW, if I use 18.0 grains of 2400 in this simulation I get 1832fps but pressures at 41,200psi and only 60% fill.

[KirkD]

Rimfire, I'll measure the case capacity and bullet length and OAL today and post the measurements here.

I figured that 2400 would give some very high pressures for 1,800 fps. I'm surprised that a load chart would use 2400 for the 30-30 and that weight bullet.

[Rimfire McNutjob]

Yeah, I'm thinking 2400 is a stretch there. Someone was reaching on that one.

In having QuickLoad scan for powder performance through a pressure and fill range, it seems 3031 comes in at or near the top in many test cases for the 30-30 and that RCBS bullet at 203 grains. I don't shoot the 30-30, but if I did I would keep 3031 handy based on these results. It seems to be a good match for this cartridge.

I just noticed in your original post that yours is a carbine. Do you want me to re-run with a shorter barrel length? Is it 20"?

[Old Savage]

Ken Waters used 29.0 grains of 3031 in a 308 Win to get the velocity you wanted with a Lyman 195 gr. in 22" barrel.

Keeping powder weight the same while changing bullet weights usually produce about the same velocity.

I think you should be close with your estimation.

[BigSky56]

Sorry 93 I duplicated your post. danny

[KirkD]

Okay, I've done my measurements and posted the data below. I don't know if this is asking too much, but I would be interested in keeping the pressure at 32,000 psi or less, so if it isn't too much trouble, I'd appreciate knowing the results for the data below, for three different inputs: 32,000 psi, 1,900 fps and 2,000 fps.

Here's my measurements:

Barrel length: 20 inches

Capacity of fire formed cases (I do not resize): 46 grains of water to the brim, flat across (no meniscus)

Weight of bullet: 203 grains

Length of cast bullet: 1.046"

Length of bullet inside case: .534"

Length of bullet outside case: .512"

Sized diameter of bullet: .308"

O.A.L. of cartridge: 2.540"

[Cimarron Red]

Kirk,

Bullets from my RCBS mould weigh 202 grains, lubed and checked. I'm loading much lighter with 5744 as I need only topple 200 meter rams with mine.

[Rimfire McNutjob]

Here we go ...

I've modified the parameters to account for your actual bullet weight, seating depth, OAL, and water capacity. The only thing I forgot to ask for was case length which I show is normally 2.039 for the .30 WCF. However, you gave me enough info to calculate it at 2.028". If it's not close to that, let me know and I will re-run. The charts below go to 18.5 inches because that's how far the base of your bullet travels in a 20" barrel.

The red hatched section of the graph is the area over 42,000psi Max Average Pressure. The purple area is between MAP-15% and and the SAAMI max of 42kpsi. The yellow area is between MAP-25% and MAP-15%. There's also a red vertical dashed line representing bullet position in the bore at Pmax. The green vertical dashed line labeled Z1 is the point where the powder has reached its progressive burn limit. The other green vertical dashed line is the point where 95% of the powder has burned. The x-axis is obviously labeled in inches of bullet travel. The graphs can also be done where the x-axis is time based.

Your original request at 30kpsi now requires 27.3 grains of 3031 to achieve 30,143psi and 1868fps at the muzzle of a 20" barrel with the new information given.

KirkD-30kpsi.JPG

Using 27.8 grains of 3031 gets you to 31,833psi and 1901fps MV. That also satisfies your 1900fps requirement.

KirkD-32kpsi.JPG

To get to 2000fps, you need 29.3 grains of 3031 for 1999fps and a peak pressure of 37,465psi. This is 94.6% case fill.

KirkD-2000fps.JPG

[KirkD]

Rimfire, you used the correct value for my case length (2.028"). I measured three different cases and chose the shortest one, figuring that would give me the highest pressure. The other two were running around 2.034", but I'm more interested in the shortest case.

One question arising out of the legend across the bottom of each graph .... The graphs say '.... 180, RCBS ...'. Even though it says '180', did the calculations use 203 grains?

A huge thank you for this fascinating info.

[Rimfire McNutjob]

Yep, 203 grains. The data line on the bottom of the graph is just showing the bullet mold from the RCBS catalog. Here's the setup page for the bullet and case info for these runs for your reference.

KirkD-Setup.JPG

This is the result window for the 27.8 grain charge of 3031.

KirkD-Result.JPG

[KirkD]

Great. I sure do appreciate what you have done. Thank you again. I will start low at 25 gr of IMR 3031 and work up from there and see how closely my actual tests match the results you have provided. If all goes well, I'll stay at 1,900 fps (if actual velocit/grains of powder matches closely the curves above).

[Canuck Bob]

I'm going to shamelessly highjack this thread. Could you please rework your program for a 32 Special? The cases are similar enough to ignore the very slight difference and the only change would be a .321 bullet. I am always curious of the difference the expansion ratio makes with these two cartridges. In the interest of full disclosure I do own a 32 Special 94 and think heavy lead like Dirk's bullet is the ticket for me.

Edit: I just reviewed the data chart and realized that I have no idea about bullet length and seating depth. Except that the equal weight bullet is shorter and seating depth is less for equal COL. I suspect this is fairly critical for the program.