Son's new Accumark .300 Weatherby withbrake and torque specs

elkeater2

Handloader
Jan 5, 2009
747
47
I don't want to write a novel, but wanted to share the experience. Rifle bought new with a Vortex scope. Scope mounted by store guy who talked a good game. Son bought 3 boxes of Wby branded 180 grain 'spitzers'. They were $36 a box, while plain brass was $35 for 20!
It shot terrible, I mean really bad. We checked the scope mount and ring screws, they seemed OK. Pulled the stock and the skim bedding around the lug was kinda sloppy so we cleaned it up. Still shot lousy. This all with the cheap ammo and brake installed.
Son purchased reloading gear for the .300, and bullets and primers.
Sent the scope to Vortex, it checked out OK. I bought an inch pound torque wrench, a good one.
It shoots now! What we did:
Weatherby has a specific torque sequence and methodology for the guard screws, including use of blue loctite. We followed that exactly. There was some bedding material which had flowed down around the front screw - enough so it could have been absorbing some recoil rhat the lug should have been receiving. Cleaned that up.
Checked the torque on the bases and rings. This has the Leupold STD front dovetail and rear windage adjustable bases. The windage screws were NOT torqued up properly, got about 3/4 turn on both of them to reach spec.
Loaded 185 Berger VLD's in carefully prepped brass fired in the rifle. 80.5 gr. H4831SC, seated to just run through the magazine.
Shot the leftover cheap ammo w/o the brake - actually grouped with mostly vertical dispersion. Great improvement! Re-installed brake and it wasn't even on the paper.
Then we shot our handloads. Voila!! We had several COL's with the same powder charge. COL didn't make much difference because they all grouped tight. I shot 3 and then my son shot 2 into the same group - just over an inch. We let it cool between shots pretty well. Then I shot 3 that went into less than 1/2". Shooting with brake or without made little difference at all.
Conclusions? ? :
Follow factory torque procedures and specs.
Don't buy cheap (even factory) ammo.
Handloading with good components and proven procedures still pays off.
Don't give up easy!
Elkeater2
 
G

Guest

Guest
Tom, it's great to see you over here at Nosler. I'm still pretty stoked you and Dave are getting that Accumark to shoot so nicely. I know it's been a frustrating road.

Oh, and of course, WDE!!!
 

DrMike

Ballistician
Nov 8, 2006
35,715
2,683
Well, it didn't qualify as a novel, but it was very informative. Thanks for sharing. I'm glad you stayed with the task at hand and sorted through the options.
 

BK

Handloader
Dec 14, 2008
4,114
89
The first thing I suspect when a rifle is spraying patters rather than groups is screw tightness. It would have been interesting to see if it was a cumulative error, or one thing was primarily responsible... I would have bet the scope was not mounted properly, and too tight can be just as bad as too loose.

I'm curious to see how well the windage rear scope base holds up to a Weatherby .30. I have one on my Whelen, and it's never given me any troubles, but I just don't trust them as much as a dual dovetail setup or Talleys.
 

FOTIS

Range Officer
Staff member
Oct 30, 2004
23,495
1,096
Same happened with my SAKO 75 in 300 RUM.

I played with the stock screw tightness and got it down to under .7" at 300 yards.
 

Oldtrader3

Ammo Smith
Nov 6, 2009
8,406
2
The only thing that I would have done diffently is to get rid of the Leupold windage screw type scope bases and replaced them with a set of TPS or some other brand Picatinny mount steel rings with steel bases and tempered steel screws. Eventually, the Leupolds windage bases will work loose again and will fail when you least expect or can afford it. I am glad that the rifle has produced good results for you so far as a result of the work that you have done and changes that you have made.
Charlie
 

SJB358

Ballistician
Dec 24, 2006
31,416
811
EE, that sounds like a great rifle. One of my good friends has the same one and wow, what a nice shooting rig. Glad you were able to get it all sorted out. I actually can't believe I have gone as long as I have without a torque wrench. I can tell after I did some swaps how lucky I actually was with screw tightness..
 

Desert Fox

Handloader
Aug 14, 2006
1,965
2
Brakes are really hard on scope and scope mounts, especially from a hard kicking magnum like the bees. If I were you, I'll replace that rings with either a Weaver style, Talley or a Picatinny style rings and base.
You should skim bed the action also and that will really get rid of that vertical dispersion. I did on mine and it really help even though I did not experienced the problem you're having. I did it just to tightened the rifle grouping.

Here's the link to my thread on the subject.

viewtopic.php?f=9&t=9866&hilit=+bedding

viewtopic.php?f=9&t=13141

And finally success.

viewtopic.php?f=5&t=17437
 

jmad_81

Handloader
Feb 14, 2007
2,937
2
Thanks you for posting this! I'm sure screw torque had something to do with my 338 WM finally shooting good. I might have to do some plaing around with with it on my 270 WSM and see if it make much difference. One day I'll get a great group, next day not so much.

Congrats on sticking with it, and getting a fine shooting rifle.
 

elkeater2

Handloader
Jan 5, 2009
747
47
Thanks for the kind words and encouragement everyone! We have another range trip coming up next weekend, hope Fotis' wind isn't blowing too much. :lol:
I think stock screw torque is more critical on these synthetics with bedding blocks than on plain old wood/glass bedded..could be wrong there.
It shot so well we don't want to mess with it too much the next couple months. More shooting should show if the rear base has problems with windage screws coming loose. Somewhere in my wayward youth I read O'Connor or Page saying "be careful not to overtighten the windage screws, they're designed to be snugged up with a quarter". Leupold says 45 in.-lbs., and that's more than I can do with a quarter...
I just didn't have time to read up on the trigger adjustments and web comments, so we'll be looking at that next week. I've successfully worked on several triggers, just not the Mark V, so am pretty sure we can make improvements there.

Elkeater2
 

JD338

Range Officer
Staff member
Nov 4, 2004
22,338
2,303
EE2,

Glad you hung with it and figured it out. Sounds like your son has a real fine shooting elk hammer.

JD338
 
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