OCW Test

[Butte Sink]

Hello All,

I wanted to get a little help here and to get your thoughts if any of you are familiar with OCW testing.
This test was done for Borden Timberline 300 RUM
Nosler Brass
Nosler 200 AB
Retumbo Powder
WLRM Primers
All bullets seated .020 off lands
100 yard target

I keep leaning towards targets #6 and #7
Target #6, both shots kissed each other dead center with whats looking like a flyer up and to the right but I do see a pretty consistent center point between targets #5 - #8, but that's just me and I'm not sure if I'm looking at right.

Any input would be great

Thanks

 

[Alex Wheeler]

Somethings not working. Vertical in every group. Lets hear more about the rifle and load.

 

[cjmac]

Somethings not working. Vertical in every group. Lets here more about the rifle and load.

I agree

 

[cjmac]

What twist barrel ?
What was the SD ?
Nothing seems consistent and groups that big and that close can be hard to tell where the common POI hits and shifts . (for me it is anyway)

 

[cjmac]

Winchester is a nasty primer . Has nothing to do with it at this point , just saying

 

[Butte Sink]

Well Hell that's what I didn't want to hear
Here some detail regarding the rifle
Make from Jim Borden
Action Timberline
Caliber 300 RUM
Barrel Hart 26" 1-10 with Borden MB

Load
Starting load 87.4
Max load 91.5
Brass Nosler
Powder Retumbo
Bullet Nosler Accubond
Bullet Weight 200 g
Bullet BC .588
Bullet SD .301
COAL 3.762
Lands 3.137
Bullet seating depth 3.117

Velocity Average done with a Megnetospeed

Groups--
#1-- 3040 / 87.4
#2-- 3055 / 87.9
#3-- 3065 / 88.4
#4-- 3080 / 89.0
#5-- 3115 / 89.5
#6-- 3125 / 90.0
#7-- 3140 / 90.6
#8-- 3155 / 91.1
#9-- 3180 / 91.7 just over max load

If I'm missing anything let me know and Thank You for the help!!

 

[Butte Sink]

Another note
All rounds showed zero sign of pressure issues
Last group #9 one round I did notice the bolt a little tight on extraction but also on that round it threw a velo at 3233 "Hot load" !! and that could have been in the powder discharge and inaccurate scale reading on my part

 

[Rsadams]

Silly thing to ask probably but sometimes we overlook the simple things...

Are the action screws torqued properly??? Same with the scope mount??

 

[Butte Sink]

Silly thing to ask probably but sometimes we overlook the simple things...

Are the action screws torqued properly??? Same with the scope mount??

Thanks for asking
Yes rifle is done correctly
Riffle is custom built by Jim Borden and I torqued the scope bases and rings myself by contacting Talley and asking them for their light weight specs
Funny factory Nosler load at 100 yards is roughly 1/2 MOA and I'm in no way a top notch shooter but I've taken a fair amount of deer, elk and speed goats in the last 30 years, my sheep is coming soon.
I just started reloading as a fun hobby and I really do enjoy it

 

[pacificman]

I might be wrong but there doesn't seem to be any consistency with the groups. I know you may not want
to hear my suggestion but if it were me I would try a different powder. I tried four different powders before
I could get my ultra shooting. Crazy thing was my rifle liked good old IMR4350...(Noslers accuracy load).
Studying your groups it seems there are flyers...(maybe not flyers but inconsistent) in just about all groups which for me in the past leads to
trying different powder and sometimes even different bullet. Maybe flyers is the wrong word...there are shots
fairly close together then one looks wide...then all wide...etc. I have had a couple of rifles give me fits in the past
but you will find what works ...ya just have to keep at it and find what your rifle likes.

 

[Alex Wheeler]

If factory loads are .5 moa, then the rifle is ok. I would start changing out components one at a time.

 

[Butte Sink]

Thanks All,

I'm going to switch up my primers to CCI and just ordered some Magnum Powder.
Nosler states it was their most accurate powder when testing, so I'll give it a shot.
I've heard so many talk that 300 RUM and Retumbo go hand n hand?
Not giving up on it and it could have been me shooting?
I'll make up a small batch and play with seating depth and see what turns up

Thanks again

 

[dsculley]

I would suggest that you load 3 each of 90, 90.3 & 90.6 and then shoot them for groups, not round robin as I assume you did in the OCW. When you see two touching and a flier in an OCW as your 90 & 90.6 many times this is shooter induced. Not saying you can't shoot, I have done it myself. The only way to know is to test that range again.

 

[mram10]

Are you shooting from a bipod, sand bags or front rest? Table or ground? Muzzle brake? I love the rum and these groups at 100 are not optimal. Retumbo is great but r33 and h1000 are my favs.

I do tests at 300 for the rum. 100 always seemed way to close for me.

Why .020 off lands?

 

[wedgy]

I would check scope adjustment, parallax, head position, cheek weld, time between shots Something is going on, reloads should shoot better than factory stuff.

 

[TZaun]

I would start by switching bullets. Those groups look like my 300 RUM when I tried Swift Sciroccos.

 

[CTK]

There is very little that could be wrong with a Borden built rifle. I assume they bedded it or was done by Tom Meredith? What contour barrel? Likely your rifle hates that combo of bullets and powder and all will be well with a change. Good news that the factory stuff shot well.

 

[Butte Sink]

I would suggest that you load 3 each of 90, 90.3 & 90.6 and then shoot them for groups, not round robin as I assume you did in the OCW. When you see two touching and a flier in an OCW as your 90 & 90.6 many times this is shooter induced. Not saying you can't shoot, I have done it myself. The only way to know is to test that range again.

My thoughts exactly and that is the plan. I'm thinking the flyers are on me, actually hoping!

 

[Butte Sink]

There is very little that could be wrong with a Borden built rifle. I assume they bedded it or was done by Tom Meredith? What contour barrel? Likely your rifle hates that combo of bullets and powder and all will be well with a change. Good news that the factory stuff shot well.

Your are correct, Tom did do the bedding on the rifle. I did order some new stuff and I'm going to work up a load and give it a shot

 

[Butte Sink]

I would start by switching bullets. Those groups look like my 300 RUM when I tried Swift Sciroccos.

Going to try powder and primers first