US869 in 270 AM and 300 RUM

[bailey1474]

Here's what I got w/the US869 and the 270 AM:

All bullets seated approx .010" off the lands (depending on how far the throat has moved). That is what they were w/my last load and it was shooting well, so I just matched it.

100 gr 3393 fps
100.5 gr 3412 fps
101 gr 3407 fps
101.5 gr 3446 fps
102 gr 3461 fps
102.5 gr 3478 fps
103 gr 3472 fps
103.5 gr 3516 fps

I had them loaded up to 104.5 but the 103.5 load showed very sticky extraction. The 103 was a little sticky, but sometimes w/these minimum taper cases if you don't pull the bolt exactly straight back, it will give the illusion of a sticky case. I think I'm going to load up 5 101 gr and 5 102 gr and see which gives me the lowest ES an SD and of course, smallest group.

I shot all of these @ 200 yds and all shots grouped very well (under 1.5") except for the first shot and the last two.

I did fire two foulers w/the WC872 load of 104 gr and it only averaged about about 3350 fps so it looks like this stuff is going to give me 50-100 fps more. Now hopefully it is more temp stable.

Also shot some US869 in my RUM w/the 210 WC. 104 gr gave me 3203 fps, 104.5 gr gave me 3227 fps and 105 gr gave me 3231 fps. I started @ 98 gr and didn't even see primer flow on these soft Federals until 104 gr so I know I'm in comfortable pressure range. I think I'll try 105.5 gr and 106 gr over the chrono. Hopefully my velocity won't jump much from the 104 gr. Then I'll load 104.5 gr or 105 gr and see what she does. Most all of these 14 shots went into 2 nodes w/the 104 gr load jumping up a good bit. The last three were around 1.5" @ 200 yds. All bullets were .010" off on this one.

Didn't play much w/the AM as I want to wait until I settle on a load for the shoot in 3 weeks but did play w/the RUM w/the 240 SMKs over 85 gr of Retumbo a bit. Took me 2 shots to center on a 12" gong @ 500 yds then 2 shots to hit the 4" gong. That is the same 4" that I ripped off w/the 210 WC last time. Hit it dead center and it spun around 4.25 rotations!!! A new "club record!!" Decided to try it again, but this time try and hit it @ 6 o'clock. I held a little lower and lobbed one @ it. I connected @ exactly 6 o'clock but the gong just couldn't take the strain. I ripped the damn thing off again!!! They're going to quit having me down if I keep tearing stuff up.

[Buffalobob]

[ QUOTE ]
it looks like this stuff is going to give me 50-100 fps more. Now hopefully it is more temp stable.


[/ QUOTE ]


Sounds good to me.

[Ridge Runner]

Bill,
How unstable is wc872?
JS

[mrultramag]

So do you think US869 and 200gr Accubond would be a good match in a factory 26" mod 700 300 rum? would one be able to match or better the approx 3150-3200 fps velocity that guys can obtain using RL25, or Retumbo? Just interested in your opinion. I haven't been able to get my hands on any US869 to play with yet. Would like to try it in 300 and 7 rum.

[Fiftydriver]

In the 300 RUM, I would suspect you would get higher velocities with Retumbo with a 200 gr bullet or lighter. As we all know though, highest possible velocity is not always the most accurate.

That said, I do feel that Retumbo would be a better all around choice for the 300 RUM simply because of burn rate and the bore diameter of the 300 RUM.

I am sure BJ is using both simply because he has the powder for the 270 AM. If it works well with both, why not use it in both!! Logical thinking and what I would also do.

Again, 869 will certainly work well in the 300 RUM but it may be a bit on the slow side for optimum burn rate to bore volume comparisions.

Kirby Allen(50)

[Fiftydriver]

Bill,

One of these days I will have to have you bring up those 270 AMs so I can look at the throats in them!! Still shootin though so give er hell!!

Kirby Allen(50)

[royinidaho]

BJ,

Good goin', for once I'm not the pioneer. Will use your data wisely when I get the opportunity.

Looks to me as though the velocities you got with from 100 to 101 grains is fast enough. I'm assuming that you're talking the WC bullet.

Question (goes w/my swiss navy project) is there any space between the bottom of the neck and the top of the powder (869) w/ 104 grains?