COAL for a .375H&H in a CZ 550 Magnum

[jbmauser]

I have been working up a couple of loads for my CZ 550 in .375H&H and noticed it has a very long throat. My hunting load consists of 300gr Barnes TSX and 71gr of RL 15. Barnes recommends seating the bullets .050 to .070 off the lands, but to do this in my rifle I have to set the COAL at 3.730(.070 off the lands). Obviously this is way beyond SAAMI max COAL spec but they fit and feed through the massive CZ action easily.

Has anyone else noticed the long throat in their CZ? Are there any potential problems with loading to this extra length?

 

[Missing Something]

I am doing the same thing. I have the bullets seated "way out" and they shoot great. As long as they sit in the magazine and don't show signs of excessive pressure, you should be OK.

I have been using Barnes Triple shock 300gr bullets and IMR4064.

 

[Freyr_255]

IIRC your pressure should go down since the case volume is larger. Problems are usually with bullets seated to deeply in the case causing increased pressure. I would say there shouldn't be any issues as long as they feed nice.

I use H4895 and have been playing with a few different bullets. Loads vary from 64-71gr depending on bullet but I haven't settled on one load as I haven't had it that long(maybe 40 rounds down the pipe).

 

[martinbns]

With a cartridge like the 375 H&H you aren't going to be hunting gophers. It's far more important that they function flawlessly and are accurate to minute of buffalo.

I would go SAAMI length and see how they shoot.

 

[Boomer]

With a cartridge like the 375 H&H you aren't going to be hunting gophers. It's far more important that they function flawlessly and are accurate to minute of buffalo.

I would go SAAMI length and see how they shoot.

X2
The length of the magazine box determines your COAL, but seat your bullets short enough that they don't hang up in the box. I habitually full length resize my brass and choose bullets with a cannelure to shoot in my hunting rifles. I use the cannelure to determine my seating depth, and crimping will uniform the bullet pull weight which is what you are attempting to do when fiddling with the seating depth. Having the round cycle though a big game rifle without a hitch is far more important than is the questionable advantage of small improvements in accuracy that might be achieved by tweaking the seating depth of the bullet, but cannot be utilized in the field. Leave that for your varmint and/or target rifles in applications where optimizing accuracy has real value.