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tambasci
12-29-2008, 03:05 PM
Hi;

Used my .30 Merrill years ago in Production IHMSA.

Does anyone have reduced loads using 200gr cast bullets (preferably with VihtaVuori powder—but any suggestions would be appreciated). Thank you.

Adrian

runfiverun
12-29-2008, 03:59 PM
if you know the parent case or one with the same capacities and a smaller bore diameter you can gather a good idea where to start.

tambasci
12-29-2008, 04:16 PM
runfiverun;

Thank you for your reply. I have access, and have used internal case capacity, and bore to determine starting loads for various cartridges.

I was hoping someone would have proven loads with that combination. Thanks again.

In case you are not familiar, the .30 Merrill is a .225 Win case opened to .30.

Cordially;
Adrian

versifier
12-29-2008, 07:30 PM
I do not use VV powders, but this formula has been used by me safely for many years with IMR and Alliant rifle powders for computing reduced loads for cast bullets from Jacketed data.
Jacketed Max Load - Jacketed Min = Difference
Jacketed Min - Difference = Cast Starting Load

Or, you can just look up .30-30 cast data in the Lee Manual or the Lyman Cast Bullet Handbook. Basically what you have is a .30-30 with just a smidge (technical term) less powder capacity. I would have no hesitation to use .30-30 data for jacketed loads in it either, if you can find listings for bullets heavier than 170gr.

Is this for a Contender?

tambasci
12-29-2008, 07:45 PM
It's for a RPM/Rock/Merrill pistol, and the 30-30 starting point sounds good to me (I'll start low). Thanks.

Adrian

tambasci
12-29-2008, 09:28 PM
By the way. I've used this formula many times to convert one weight bullet to another weight. The guys may find it useful:

BULLET WEIGHT FORMULA

To calculate how much to increase or decrease a powder charge when increasing od decreasing a load’s bullet weight—while keeping the pressures the same:
Divide the old powder charge weight by the weight of the old bullet.
Multiply that result by the difference between the old and new bullet weight.
Multiply that result by 0.375. This equals the change in powder weight, either plus or minus depending on whether the new bullet is lighter or heavier than the old one.
For example, suppose the existing load consists of 54 grains od Brand X powder behind a 180 grain bullet and you want to substitute a 220 grain bullet. How much should the powder charge be deceased?
Divide 54 by 180 = .3
Multiply .3 by 40 grains = 12 grains
Multiply 12 grains by 0.375 = 4.5 grains
Since bullet weight is being increased, the powder charge must be reduces by 4.5 grains.

runfiverun
12-31-2008, 01:42 AM
i have heard of the merill.
but could not recall the case it was based on. [i was thinking the 220 swift]
and with vitavouri powders i was not even gonna guess.
with hodgdons or even imr or accurate powders i am good, and have data.
and can give you quite a few loads for a 30-30 cast boolit.

tambasci
12-31-2008, 10:57 AM
Certainly would appreciate that. The heavier bullet the better. Thanks.

"A"

runfiverun
12-31-2008, 06:45 PM
aa-2230 24-26 grs with a 170 gr boolit. 25 with a filler very accurate
h-414 36-39 grs ............. same. [ 38 grs a fave load for hunting with a 150 flat point]
these run about 37k [cup] max pressure.

180 gr boolits

rl-7 20-26 gr 1650 fps-2050 fps
imr 3031 22.5-26 gr 1625-1950
w-748 23.5-33grs 1650-2175fps.........good cast powder
h-335 22.5-29.0 1628-2175 fps
w 760 28.5-35.5 1625-2125 fps about 35 is a case full and this is a very good balanced load right at the edge of being too slow of a powder.
all these loads are under 35k [cup] for pressure
for 200 gr loads cut the 180's by10% and work up.
hope these help, i probably have others too but they are ones i have made up and have no data to back them up.

tambasci
12-31-2008, 11:34 PM
Thanks!

A

WolfTrap
01-20-2009, 02:14 AM
Hi;

Used my .30 Merrill years ago in Production IHMSA.

Does anyone have reduced loads using 200gr cast bullets (preferably with VihtaVuori powder—but any suggestions would be appreciated). Thank you.

Adrian
Here's a load I've used for the past 20 years using 30 Cal. 165 RCBS Silhouette GC......25gr. H322 and 24gr Reloader 7 both using standard primers.
Both were easy 40's with rams hitting the deck hard!
As for the 200gr.......way too much punishment going the 40!
To be honest.....both my Merrill and TC in the 30 Herrett was my most used Cals in IHMSA/NRA Production/Standing classes.
WT
PS:RPM listing for the 30 Merrill @!200gr Jacketed was Win 748 30.0-32.0 grains....Good luck!