7mm rum ai

[TwoMore]

First post here . I know I am going against the grain but I am a .284 nut. I just finished up a 7 RUM AI build that I decided to do because of the 195 berger. took it out to run some ladder tests with wc 872 and rl 33 got to my range and someone stole my bench!!! so please forgive my tailgating shooting lol first off it is a model 700LA with a 30 inch Krieger 5R my reamer is a .3164 neck with .949 bore rider, after my break-in ,I started with ladders of 92 to 97 grains of wc 872 and the same with rl 33 my lot of 872 seems to be on the faster side it showed signs of pressure at 97 grains (ejector mark and slight drag on the bolt) but hit 3293 on my Magneto speed. seems to love 95 grains of 872 at 3255, went thru the rl33 loads and never hit pressure.. gunna go this weekend to try 98+ to find my pressure. the 33 ended up at 3283 at 96 grains , the 97 grain round did not record because I didn't get the magspeed back to the main screen when I was lookin at the archived speeds of the 872.
The group is all ten rounds in my ladder test with the bottom loads hitting 3178. It seemd to group close but as i started to get the speed up it started to one hole with 7 rounds in it, with just some vertical differences. the rusty bullet hole with the circle around it was already there and that is what I was holding . looks like i am going to be right at 3300 fps with it gun) i will be testing same loads for ES this week end and hittin the 600 yard target

 

[Lefty7mmstw]

Nice!!
It's good to see someone having the 195's work well for them...

 

[Rich Coyle]

Congrats on your project's apparent success.

 

[TwoMore]

Thanx , we had some pretty nasty weather last night and some trees down so I wasn't able to get to the 600 yard targets but I did do some more 100 yard work, looks like it is going to settle in 94 to 95 grains of rl33. I really would like the brass to last a bit ,I did some pressure testing with 97 98 and 99 of rl33 ...97 went 3310 with a slight ejector mark no drag, 98 only 10 feet faster it went 3320 with a bit more mark, probably should have stopped there lol but the 99 went 3355 and I had to fistbump the bolt open and it gave that case a shiner and loose pocket. when I measured the 97 and 98 grainers the case grew at the back a tad and the primers seemed to go in a good bit easier when I checked them, so i just think 96 of rl33 will be the top of the load for that rifle. it was also 92 degrees today , my goal was 3225 -3250 with this build so I think I will stay with that and save brass

 

[gohring3006]

First post here . I know I am going against the grain but I am a .284 nut. I just finished up a 7 RUM AI build that I decided to do because of the 195 berger. took it out to run some ladder tests with wc 872 and rl 33 got to my range and someone stole my bench!!! so please forgive my tailgating shooting lol first off it is a model 700LA with a 30 inch Krieger 5R my reamer is a .3164 neck with .949 bore rider, after my break-in ,I started with ladders of 92 to 97 grains of wc 872 and the same with rl 33 my lot of 872 seems to be on the faster side it showed signs of pressure at 97 grains (ejector mark and slight drag on the bolt) but hit 3293 on my Magneto speed. seems to love 95 grains of 872 at 3255, went thru the rl33 loads and never hit pressure.. gunna go this weekend to try 98+ to find my pressure. the 33 ended up at 3283 at 96 grains , the 97 grain round did not record because I didn't get the magspeed back to the main screen when I was lookin at the archived speeds of the 872.
The group is all ten rounds in my ladder test with the bottom loads hitting 3178. It seemd to group close but as i started to get the speed up it started to one hole with 7 rounds in it, with just some vertical differences. the rusty bullet hole with the circle around it was already there and that is what I was holding . looks like i am going to be right at 3300 fps with it gun) i will be testing same loads for ES this week end and hittin the 600 yard target

And...... The barrel is gone!!!!

Just kidding.... Very interesting chambering

 

[TwoMore]

lol I hear ya , I have a bunch of 300 brass for a 300 rum another 7 rum and a 338 EDGE this rifle actually has another barrel that I can change out in a few minutes (338 Edge) when i swapped barrels to this one surprisingly i was only 6 minutes high and 3/4 minutes right with the scope at 100. I actually re chambered an old 7 rum sendero barrel that never shot well, that i put on this frame to fire form with i took off 3/8 inch to get the neck right.

 

[TwoMore]

something about a 7 rum that just never was real efficient, and i have been shootin one since Remington came out with it, with this 195 and slower powders just made me want to try...

I have had a pair of stw's, one was one I re-chambered from a blued laminated sendero the other i bought in a stainless fluted sendero

 

[gohring3006]

For a hunting rifle. Couple shots a years it will be fine.

 

[Lefty7mmstw]

something about a 7 rum that just never was real efficient, and i have been shootin one since Remington came out with it, with this 195 and slower powders just made me want to try...

I have had a pair of stw's, one was one I re-chambered from a blued laminated sendero the other i bought in a stainless fluted sendero

yup... they start to turn on with the heavies... my 7rum tosses 180sierra's at 3100 fps with start loads of retumbo.. 26" lh lss.... 1/2 moa

 

[TwoMore]

For a hunting rifle. Couple shots a years it will be fine.

ima beat the brakes off of this thing see what its got, got a 1600 yard target callin it out. gun) may wear it out to quik but that is the fun of it for me.

 

[TwoMore]

yup... they start to turn on with the heavies... my 7rum tosses 180sierra's at 3100 fps with start loads of retumbo.. 26" lh lss.... 1/2 moa

I have a rh sendero that likes the 168s and 180s it is factory and i get about 5/8s out of it. I did a 338 edge that I love (this rifle) that I used a bore rider on, it picked up a good amount and the first thing that popped in my mind was a big 7 I could use that action-ed chassis on, a 195 and wc ,,just hopin my brass pile dont take to bad of a beatin lol i am runnin my edge with tame loads of H1000 and it is runnin a tad over 2900 with a 300 otm and is easy on brass

 

[gohring3006]

It would be interesting to document the round count. Just to see when it goes with your type of shooting.
The heavy bullet with the slow powders would help. Then is would be nice to have another barrel that only has Hex coated bullets thru it and see if there is a significant difference.
It's not a scientific test, just because no two barrels are the same. But allowing for a couple hundred round margin is enough for me to see there is a difference.

 

[TwoMore]

i definitely will be documenting this barrel for sure

 

[TwoMore]

Well shot a few hundred thru it so far, took it out yesterday and set up at 420 yards, clean barrel, needed to do some shooting with a wsm also , beautiful day, been a bit cooler got to the bench set up, shot a three round string , I could see it was drillin, drove down to my target peeled that one off put a new on up went back to the bench fired one more then put it up and got the wsm out lol load is 195 eol 94 grains wc872 .005 jam 3200 fps ,those were 3rd fired brass, pockets stayin tight, the 10 ring on that lil target is 1 inch. first shot was the low shot, next three were .641 windage .526 elevation, with the first shot added in it was 1.096 elevation .741 windage the first shot was 3150 fps. needless to say i am real happy with it