I've been using this recipe from hodgdons reloading. At 71 g I'm compressing the powder. So at 73.5 I'll be compressing the chit out of it. I know that COL didn't mean much , but I wanted to follow the book until I get a good enough group to work around. So , what you think? Load them to max?View attachment 44514
7MM mag compressed loads???
- Thread starter Brianma65
- Start date
Purple shoulder
Regular
- Location
- Winnipeg MB
I have no experience with retumbo but I have found with my 300wm and H1000 that if I hold the case against my running scroll saw and slowly pour the powder in I get about 3 more grains in. Vibrating it after pouring it in did nothing but while slowly pouring it in works quite well. It takes a bit of time but I dont mind.
If you have a vibratory tumbler, holding the case atop it for a bit works as well.
I have been using H1000 with 69 grains and 150g bullets in my 7mm MAG as its preferred diet; it's an older Parker Hale with a slow twist. I've never tried compressed loads, I'm not sure I want to start, either.
I try to use compressed loads in every cartridge I load for.........except my old Winchester lever guns......I find compressed loads to be the most consistent over the chronograph and have the least extreme spread and usually the best accuracy. In all my bolt guns I only work with powders that will give me this. It also completely eliminates any possibility of powder bridging and carrying over in the funnel or double charging or weird light or heavy charges in my cases as the powder is plainly visible and comparable it the case necks when all the cases in the tray are charged.
I have found all the Hogdons , IMR and Winchester powders to be very agreeable with compressed loads and very predictable with no changes due to compression, however the same cannot be said of Alliant Reloader series of powders. They tend to become unpredictable after about 105% load densities with large capacity cases, I have found this with RL 17, RL 19, and RL 22. I have yet to work with compressed loads of RL 15 or 25, or any of the newer RL series 'cause they just ain't available here yet, maybe, ever...............
I have found all the Hogdons , IMR and Winchester powders to be very agreeable with compressed loads and very predictable with no changes due to compression, however the same cannot be said of Alliant Reloader series of powders. They tend to become unpredictable after about 105% load densities with large capacity cases, I have found this with RL 17, RL 19, and RL 22. I have yet to work with compressed loads of RL 15 or 25, or any of the newer RL series 'cause they just ain't available here yet, maybe, ever...............
Purple shoulder
Regular
- Location
- Winnipeg MB
Yes. Prolly not the perfect powder for the 7 mag.
Nothing scary about compressed loads.... Only time I'd double check things is if you find you have compressed loads and the manual doesn't identify it. Some military brass can be pretty thick and have reduced capacity...
Check your loads against Barnes....Retumbo doesn't show up until 160gr but max is only 61.9 for the 160gr.
http://www.barnesbullets.com/load-data/
Check your loads against Barnes....Retumbo doesn't show up until 160gr but max is only 61.9 for the 160gr.
http://www.barnesbullets.com/load-data/
Where ??
- Location
- Western Manitoba
I do not see on your post what brand of case the data was listed with, nor what brass you are using. I've seen at least 2 grains or more capacity difference among different brands, which would make a difference regarding your compression issue. Goes back to the validity of the pressure tested data - only useful if all components are identical.
View attachment 44547
I'm using FC cases.
Yep, I know but have yet to get my hands on any...........did get some RL 23 and 33 the other day but haven't tried it in anything yet.........
