300 wby help

[Catskills]

My Mark V loved factory 165g Interlocks....shot one hole groups regularly. It shot nearly as well with 180grain factory Interlocs but hated partitions. Hand loading was a disappointment. Could never match factory velocity and accuracy (had the same challenge with a 340). I was able to get 200grain accubonds to shoot moa with a stiff charge of MRP. I was also able to get 180 Gamekings to do the same with 7828. However, I could do no better. Interestingly, 180 Partitions would never do better than 2 moa with MRP or 7828. One of these days, I want to play around with RL26 and the 180s/200s. I tried old style X bullets which were abysmal. Overall, I've found the Mark Vs frustrating to load for because they could both shoot some factory fodder into one hole groups....so the accuracy was there....I just couldn't duplicate it. Funny thing is if I'd never seen the accuracy potential, I'd have been content with the moa groups I did find.

 

[tgeavenson]

I use h1000 for my. 300 weatherby. It shoots lights out. Barrel is a 3 groove lilja.

 

[9x23w]

Have you checked the throat length? Years back the SAAMI standard for the 300Wby included a long throat, which enabled Weatherby to boost velocity a little. Not really helpful for best accuracy.

 

[Toddxusmc]

I have seen great advice from alot of people but what I haven't seen is a recommendation for checking the action screws(unless I missed it somewhere in all the replies). Action screws must be tight and torqued to the proper specifications or you won't get good groupings. Specifications will vary between the type of stck material as well as bedding material. The fact that factory loads won't shoot well indeed indicates a problem although I don't know how many DIFFERENT types of factory ammo you have shot. The amount of freebore is generous in WBY to say the least. I had a MK V in .300 Win that had .257 in freebore from the mouth Of the case to the lands; very difficult to load for. You may want to ask your gunsmith how much freebore he put in your barrel when it was chambered, you might just have a rifle that is finicky in CBTO length. If that's the case you will just have to take a load that shoots halfway decent and play with the CBTO length to determine the sweet spot.

 

[Eric Alexander]

Hi there, I have a Montana rifle in 300 wby, I just had a #3 Bartlien barrel installed by a very good gunsmith. It has a great tigger and is bedded in the factory Montana stock. I broke the barrel in per the instructions. H-4831, IMR 4350 and a box of factory wby 180 ammo. I can't get the gun to shoot! It's a 1 in 10 twist. I cleaned real well with CR-10, then ran JB Bore Paste down the barrel, then cleaned again and oiled. the bullet I'm trying to get to shoot is a 168 accubond long range. The scope is a 4.5x14 leupold, Warne bases and Leupold PRW rings. I loaded a bunch more with IMR 7828, R-19, and AA-3100. Now, by the way, during break in the barrel was very very filthy. I'm hoping that the JB Bore Paste helps. I seat the bullets so it clears the magazine for magazine clearance purposes. All bases, rings and scope are top notch and tight. I'm told that IMR 7828 is the go to powder? Any tips? Maybe takes awhile to break in? I'm letting the barrel cool after a few shots as well. Thanks for any tips at all to get this going.

It seems you have all the correct elements. The only question that presents itself to me is how far off the lands is your bullet seated?

 

[Eric Alexander]

I've done 80.5gr IMR 4831 with a 167gr Peregrine, 81gr IMR 4831 with a Barnes 168gr TTSX, and 80.5gr IMR 4831 with a 175gr Barnes LRX. Never used RL-22 with my .300 Wby, but I have in my .340 Wby. The 265gr LRX with RL-22 was shooting pretty good for me.

I've just acquired a W'by Mk V in .340 so I am interested in your load for the 265. I'm going to try the new Nosler 265 ABLR. Do you mind sharing seating, oal, powder weight, primer.
gracias

 

[Draftmule]

Most likely has already been suggested but LRAB seating usually improves with more jump than less.

 

[NielsC]

So do you think it is the rifle? Just saying.

 

[SSG Graybush]

Hi there, I have a Montana rifle in 300 wby, I just had a #3 Bartlien barrel installed by a very good gunsmith. It has a great tigger and is bedded in the factory Montana stock. I broke the barrel in per the instructions. H-4831, IMR 4350 and a box of factory wby 180 ammo. I can't get the gun to shoot! It's a 1 in 10 twist. I cleaned real well with CR-10, then ran JB Bore Paste down the barrel, then cleaned again and oiled. the bullet I'm trying to get to shoot is a 168 accubond long range. The scope is a 4.5x14 leupold, Warne bases and Leupold PRW rings. I loaded a bunch more with IMR 7828, R-19, and AA-3100. Now, by the way, during break in the barrel was very very filthy. I'm hoping that the JB Bore Paste helps. I seat the bullets so it clears the magazine for magazine clearance purposes. All bases, rings and scope are top notch and tight. I'm told that IMR 7828 is the go to powder? Any tips? Maybe takes awhile to break in? I'm letting the barrel cool after a few shots as well. Thanks for any tips at all to get this going.

If the scope is new, swap it for a known good scope. Torque everything to spec, action screws, base and rings/get a fat wrench if you dont have one. You should test jumps not just run it at mag length. Find the right jump and do a chrono ladder test/satterlee test. And combine jump and speed nodes and see if it has good accuracy. If its over 2.5 inches it definitely could be the scope, Ive gotten 3 bad new cheaper scopes and seen a bad brand new Razor at the range. Guy was about to send his rifle back to CA and I suggested he swap scopes with his buddys and his groups went from 2.5 to .6 just like that. The H4831 should work well with the 168 to 180 gr bullets. And RL22 for the 190. H1000 for 200+ gr bullets. You may want to try a Berger Hybrid or CH as they tend to like more jump then AB's. The easiest bullet to tune is the flat base Hornady 150 gr Interlock, #3031 and it shoot well at book coal. I found 72.7 grs of RL 16 at 3.36 coal shot .44 inch 5 shot group at 100. I loaded only one test sample just to see if it would shoot in my 300 wm cuz the bullet shot so well in every other rifle Ive loaded it for, and it did absolutely but I didnt go back and chrono it. But for hunting <500 the flat base low bc bullet would be fine.

 

[Tikka300man]

Hi there, I have a Montana rifle in 300 wby, I just had a #3 Bartlien barrel installed by a very good gunsmith. It has a great tigger and is bedded in the factory Montana stock. I broke the barrel in per the instructions. H-4831, IMR 4350 and a box of factory wby 180 ammo. I can't get the gun to shoot! It's a 1 in 10 twist. I cleaned real well with CR-10, then ran JB Bore Paste down the barrel, then cleaned again and oiled. the bullet I'm trying to get to shoot is a 168 accubond long range. The scope is a 4.5x14 leupold, Warne bases and Leupold PRW rings. I loaded a bunch more with IMR 7828, R-19, and AA-3100. Now, by the way, during break in the barrel was very very filthy. I'm hoping that the JB Bore Paste helps. I seat the bullets so it clears the magazine for magazine clearance purposes. All bases, rings and scope are top notch and tight. I'm told that IMR 7828 is the go to powder? Any tips? Maybe takes awhile to break in? I'm letting the barrel cool after a few shots as well. Thanks for any tips at all to get this going.

IMR 7828 is a great powder for the 300 Wby and I've found that A 3100 shoots lights out in every rifle I have although it doesn't give top velocity. Perhaps my favorite powder is RL 22 though, great combination of accuracy and velocity and after all, velocity is a big part of the draw for that caliber. I would try about 5 or 6 different bullets (plain spitzers are fine) along with A3100; if you can't get any of them to shoot good groups then it's time to take it back to the gunsmith. I've never shot a bad group with A3100 in any caliber so if it doesn't work, then you need to take it back and have it checked.

 

[.300 Dakota]

Try Barnes bullets. They are sometimes the only thing that will shoot in that over-bored throat. Having said that. I have a similar issue with a 6.5 PRC on a Winchester action and Bartlein barrel. My old gunsmith wouldn't use Bartlein before he passed away. I am hearing they are not all created equal... While the vast majority of match shooters still use them, they know what they have before they go in to a match. If the Barnes doesn't work, I recommend going to a Brux, Krieger, or Hawk Hill barrel and chambering it in .30 Nosler or some of the Sherman fodder everyone is raving about to get the same performance. The Weatherby chambers are notoriously finicky because of all the free bore. Even Ken Waters noted this in his "Pet Loads" book. I can tell you, because I've tried them all- the .300 Dakota will best them all for accuracy. The problem is getting great brass consistently. Everybody says Reloader 26 fixes everything. If you can find any, try that with a Barnes TTSX. I would try both regular and mag primers to see which does best, but a powder that slow needs a mag primer for consistent ignition.

 

[asd9055]

Try Barnes bullets. They are sometimes the only thing that will shoot in that over-bored throat. Having said that. I have a similar issue with a 6.5 PRC on a Winchester action and Bartlein barrel. My old gunsmith wouldn't use Bartlein before he passed away. I am hearing they are not all created equal... While the vast majority of match shooters still use them, they know what they have before they go in to a match. If the Barnes doesn't work, I recommend going to a Brux, Krieger, or Hawk Hill barrel and chambering it in .30 Nosler or some of the Sherman fodder everyone is raving about to get the same performance. The Weatherby chambers are notoriously finicky because of all the free bore. Even Ken Waters noted this in his "Pet Loads" book. I can tell you, because I've tried them all- the .300 Dakota will best them all for accuracy. The problem is getting great brass consistently. Everybody says Reloader 26 fixes everything. If you can find any, try that with a Barnes TTSX. I would try both regular and mag primers to see which does best, but a powder that slow needs a mag primer for consistent ignition.

I have a few WBY 300. Three with approximately the same barrel length. One is Japanese, mid 80's one was made around 2016 and one around 2008. I can shoot the 200 AB or PT or the 180 TSX in any of them, same load, same seating. Killers! Maybe I got lucky. I have a 60 year old, only shot 180 BT in that back in the day. Was happy and never tried anything else. Finicky? Maybe, or maybe need to understand the rifle/load

 

[nksmfamjp]

Let's start with the old rifle....First, the old barrel didn't shoot well, so you are replacing it. I'm assuming it was a Montana barrel? How bad was it? What did groups looks like? Was it 2 shots in one group and 3 in another, or flyers?

Now the new......the barrel and scope are new, right? Muzzle brake? Anything else changed? Are the brass new with the new barrel?

Rest.....What kind of rest are you using? What are the best groups you have shot off it with any rifle?

 

[asd9055]

Let's start with the old rifle....First, the old barrel didn't shoot well, so you are replacing it. I'm assuming it was a Montana barrel? How bad was it? What did groups looks like? Was it 2 shots in one group and 3 in another, or flyers?

Now the new......the barrel and scope are new, right? Muzzle brake? Anything else changed? Are the brass new with the new barrel?

Rest.....What kind of rest are you using? What are the best groups you have shot off it with any rifle?

Back to basics!!!!