[chrisf]

I loaded some 260 grain Cast Performance Bullets using 34 grains of Reloader 7.  My chronograph shows an average of 1,950 fps.  The bullets are .376 diameter and have a gas check.


Can I get more velocity out of this bullet using this powder or is this about the top end?  I'm not showing any pressure signs.

 

[mattc1]

I think you might be close to the end of the road with that combo.  For heavy cast bullets in my Win BB 94 .375 I've switched to AA1680 and I use .38-55 brass, which gives about 3-4gr more case capacity.  Still working on load development, but I think others on this board could give you more details about their experiences with this combo.

 

[chrisf]

Thanks for the response.  Accuracy seems to be good with this particular load so I'm thinking about trying it this weekend.  I figure this load has plenty of punch for deer and hogs so I doubt I will try to get anymore out of it.

 

[Jimmy]

Matt,

What trim length do you use for the 38-55 brass in your 375 Win BB?  I too have an older model and want to use this brass... I have heard some using the 38-55 trim length, but am hesitant to do that, guns are too expensive for me!

Thanks, Jim B

 

[bartmasterson]

Chrisf,

I have no experience with the Cast Performance bullets in this caliber.  But using the BTB 250 gr LFNGC over 35.7gr of Re7 in 38-55 cases I get 100 fps more out of my Marlin than what you're seeing.  I get the same velocity using 35.5 gr of Re7 in fireformed 30/30 cases.  These are sized to .377.  I've only had to trim the 38-55 cases once and then I used the trim-to-length for 38-55 (2.118 I think).  Of course there are a lot of variables here so don't try this without easing into it.


In a posting regarding max velocity for the 375 Marshall mentioned that AA1680 produced the top velocities in his tests.  I have yet to try it.  One of his loads that I recall (using Re7) ran at about 2250 fps.  These postings are buried somewhere down in this forum (see page 5 for one of them).



(Edited by bartmasterson at 8<!--emo&:0--><img src="http://beartoothbullets.com/iB_html/non-cgi/emoticons/wow.gif" border="0" valign="absmiddle" alt=':0'><!--endemo-->3 am on Nov. 17, 2001)

 

[oldpete]

All,
I have a Ruger #3 in this Cal. and use a 260gr. Gas check sized .377. My most accurate load to date is 32gr. of 3031 with the bullet seated to 2.59" . This load groups under 2" at 100 yds. 1 have been up to 34gr. of 3031 but that load is compressed (alot).
My next try will be with #1680 and i will keep you posted.
I have used up to 36gr. of #1680 with the 220gr. Hornady with no problem and still working up slowly.

oldpete