Reload Help- Any reloaders?

[Stevotary]

I'm fairly new to reloading. I have 300 win mag that I am reloading for. I worked up loads with IMR 7828, hornady spent casing and Hornady Interlock 180 gr BTSP. I went in increments of 100 fps starting at 64.2gr-2500fps, 67gr-2600fps, 69.7gr-2700fps, 72.4gr-2800fps, 75.2gr-2900fps. I didn't really know what to look for when figuring out what was too hot, so i just went up and saw which fps grouped the best. There wasn't any obvious damage to the casing. I ended up going with 74.9gr, which is supposed to be 2850fps. I realized I am supposed to be looking for indentions on the back of the bullet. I noticed that all the bullets at 74.9gr have a slight full moon mark.

Does that mean the load is too hot?

Have I done damage to my gun? I can't get it to group very well.

[chief longshaft]

Bulletsor brass. If it over pressured the primer will be pushed to the back and look flat

[muddyfuzzy]

a flat primer and a hard extraction are good signs of high pressure. also check the brass in front of the belt. this is where this cartridge stretches the most, if you start to develope a bright band there that signals it needs to be tossed. the 7828 is a very slow burning powder which is it's strong suit, i never really liked in my .300 and had better luck with imr 4350 and ended up giving the 7828 away.
my old .300 performed best at around 2850-2900 but its really all about case capacity. in a perfect world you want to get the most powder you can in the case with a safe operating pressure. this will promote consistant start-up pressures and uniformity lending to better accuracy.
you did the right thing working up, if the higher volume charges show none of the signs listed above then rock on with what shoots the best.
just for giggles what primer are you using?

[Stevotary]

a flat primer and a hard extraction are good signs of high pressure. also check the brass in front of the belt. this is where this cartridge stretches the most, if you start to develope a bright band there that signals it needs to be tossed. the 7828 is a very slow burning powder which is it's strong suit, i never really liked in my .300 and had better luck with imr 4350 and ended up giving the 7828 away.
my old .300 performed best at around 2850-2900 but its really all about case capacity. in a perfect world you want to get the most powder you can in the case with a safe operating pressure. this will promote consistant start-up pressures and uniformity lending to better accuracy.
you did the right thing working up, if the higher volume charges show none of the signs listed above then rock on with what shoots the best.
just for giggles what primer are you using?

CCI 250. Does primer make a big difference? I'm out of the IMR7828. I think I'm going to go to H4350 with a Berger 185VLD. I'm setting up a 1000yard gun.

[muddyfuzzy]

CCI 250. Does primer make a big difference? I'm out of the IMR7828. I think I'm going to go to H4350 with a Berger 185VLD. I'm setting up a 1000yard gun.

primer brand can make a huge difference. for me cci was a little hotter of a primer at least based on chrono results. i had my best luck using the winchester primers in my .300 loads. as they seemed to give me a more stable velocity. i don't have any exp, with the hodgdon powders so i can't say anything about them good or bad. i've reloaded the .300 for 15 years, my fil for 30 and we both get really good results with the imr4350, the 4831 to a great powder as well in the .300 win.

[PSD Ryan]

Maybe it's slightly loose primer pockets, but when I was doing my workups for my AR, even the minimum recommended loads gave me flat primers. I don't know how great that indication really is.

[yanta61]

I would research "latter test" and start there when trying to work up any load. I would start at 10% under max charge and then start your way up with 1/2 grain increments. The further you are from the target the better when doing a latter test. I did mine at 500 yards. Just make sure each shot is consistent and the test will show you what charge your barrel likes. Remember that max charges are not always the most accurate ones. The load that I picked for my 308 was on the low side. I’ve shot ½” moa groups out to 600 yards so far. At 500 yards while doing the second part of the latter test. I picked 42gr, 42.5 gr. And 43 gr to do my final group shots. @500 yards the 42 gr was about 5” group, 42.5 gr was about 2” group and 43 gr was about 6” group. Picking the max charge might get you by but will never show you the real performance of the rifle.

[mikeb1206]

the 4350 is the way to go with the 300, I also use it in my 30-30 and 30.06.

[muddyfuzzy]

the 4350 is the way to go with the 300, I also use it in my 30-30 and 30.06.

i actually run 38.0 grains of it in my .22-250, go figure.....who would have thought! loved it in my winmag too.

[nzwermann]

I use cci primer and use alligant powder. Right now I am reloading 45 acp 230gr bullet hallow point with a 8.5 load. My Springfield XD 45 loves it. I have found that cci primer and alligant powder to work the best. I would suggest you get some reloading books that has the bullet and grain you want to use. They show what the best load is for that bullet. If have a few books I could get you some information if you like pm me or email me at nzwermann@gmail.com. I plan to get into 270 win rounds just need to buy the die and powder for them....