175 cast loads

taz · May 06 2015 08:46:53 PM MDT

Hello I have been away from shooting for a while now. I would like to get back into shooting steel plates. I cannot get anymore 231 powder for this gun. I have a fair amount of Vihta Vuori N 340,winchester primers, a mixture of R-P and widway brass.The bullets are 175 grain cast swc's.The gun is a Delta Elite with a 6" comped barrel . All my reloading data went away in a "fire sale".
I have seen this load somewhere but have not been able to find it again. Any help you fellows can give for a starting load will be appreciated.
Vihta Vuori does not list a load for a cast bullet and the closest is a 180 hp speer with 5.6 startinlg load. How close is this to start with SAFELY?
Thanks

bjw0007 · May 07 2015 04:59:26 AM MDT

You should be able to use jacketed hollowpoint data for cast, but work up slowly. Cast loads are *supposed* to generate lower pressure given same charge and projectile weights. On top of that, you are using a shorter projectile, which will generate lower pressures.

I use hollowpoint data all the time for my cast loads. Just work up slowly, and know what your target velocity is.

-Ben

sqlbullet · May 07 2015 08:57:53 AM MDT

I run 180 JHP data with cast bullets all the time without issue. Reduce 10% and work up. As has been said, you should have a good bit of extra headroom because of reduced bearing surface and reduced friction of lead versus copper.

I load a lot of blue dot and unique under 175 grain SWC. I would be interested to hear your results.

taz · May 07 2015 09:58:02 AM MDT

Thanks for the info . Will start working up these loads ASP. May be a week or two .
Thanks again

The_Shadow · May 07 2015 09:58:16 AM MDT

This might shed some light on your loading situation Lyman #48

taz · May 07 2015 10:01:24 AM MDT

Thanks Shadow It has the starting load with the bullet I am shooting.
Thanks again

taz · May 18 2015 09:18:12 PM MDT

OK I made it out to the range today with two loads to start with
First load using 175 gr bullet same as #401638 6.3 gr N340 10 rounds throw out hi and low and average of 8 was 1180 fps power factor of 205143 with my cronograph
Second load same bullet 6.5 gr of N340 ave 1208 fps power factor 211421. As you can see it is way to hot of a load for plinking and shooting steel. I am thinking of dropping down to 5.8 or 6 gr of N340 . Would this be too much or am I stuck with what I have? I would like to be around 1000 fps or less. I am not looking have some one stick their neck out , just a good answer.
Thank you

Taterhead · May 18 2015 09:49:18 PM MDT

Thanks for sharing the results.

That is quite a bit of velocity gain over the book data. Some of that is likely due to the barrel length. Are you absolutely sure about the charge weights? If so, I'd just do load workups in reverse. Step down in 2/10th increments until you get where you like. The pressure curve will likely start dropping quickly so you might not need to reduce as much as you think you do. I'd be interest in hearing your results.

taz · May 19 2015 09:50:57 AM MDT

Taterhead Yes very sure about the charge weight, after I get the weight I need I put 3 charge weights on the scale and get it so there is less than a gram diference . Will start dropping down on the weighs and will let it be known how I make out.
Thanks

sqlbullet · May 19 2015 10:24:58 AM MDT

Quote from: taz on May 19 2015 09:50:57 AM MDT
Taterhead Yes very sure about the charge weight, after I get the weight I need I put 3 charge weights on the scale and get it so there is less than a gram diference . Will start dropping down on the weighs and will let it be known how I make out.
Thanks

I sure hope you meant a grain of difference. 1 gram = 15.43 grains, so 1 gram of difference is almost a triple charge.

taz · May 19 2015 04:35:04 PM MDT

Yes ment 1 grain fingers were not awake yet !!!!!

Taterhead · May 19 2015 10:29:27 PM MDT

Quote from: taz on May 19 2015 09:50:57 AM MDT
Taterhead Yes very sure about the charge weight, after I get the weight I need I put 3 charge weights on the scale and get it so there is less than a gram diference . Will start dropping down on the weighs and will let it be known how I make out.
Thanks

Doin' a bit of quick math...

If you are as much as a grain off with 3 charges, that would be more than 3/10ths per charge. That is a lot for a quick-burner. But I'm probably not following what you're saying.

taz · May 20 2015 10:11:46 AM MDT

Taterhead if my load is 6.3 grains my toatal weight for three is 3x 6.3 =18.9 .That tells me that my scale for one load is right on at 6.3 grains of powder. I hope I am explaining this properly.

taz · May 29 2015 10:03:14 AM MDT

Hello again Back out to the range with two more loads
175 gr swc 5.9 g N340 10 rounds ave vel 1147 pf 200725
175 gr swc 6.1 g N340 !0 rounds ave vel 1169 pf 204575

Still too hot for what I want ,will down load some more, brass lools good ,no flattened primers etc.
Did find aload for a 180 HP speer with N340 start load of 5.6 with max load of 6.4 So I think I still have some rome to play with.
Wish me luck

taz · June 06 2015 10:16:12 AM MDT

Friday out to the range again
175 g swc 5.7 g of N340 10 rounds ave vel 1082 pf 189399

175 g swc 5.5 g of N340 10 rounds ave vel 1069 pf 187140

looks like I will go with 5.5 g of N340 for now until I can find more load data . May drop down a bit more later on.
Thanks for the help everyone