Trying to replicate the Weatherby load

[Don458]

Weatherby 240 85 gr TSX my favorite load (discontinued now only offer 80 gr ttsx) Reloaded some rds , max load is 50 gr IMR 4350. according to Barnes data -3500 fps like factory ammo. Loaded up some starting at 48 gr and up . All had sticky bolt ( hard to open) got to the 3500 fps I wanted, groups were fantastic at 200 yds - 3/4 “ But hard to open bolt. Smack it with hand . Lower loads at the 48 gr level- (3330 fps) still hard to open bolt and groups opened up to about 2-2 1/2 “@. 200 yds . There are No over pressure signs on case not even extracting mark primers look good too ? So im trying to keep it at factory load velocity. All cases Full length resized, Case first trimmed to 2.490”. Than I trimmed some down to 2.485” thinking maybe it will help. Col -3.100” Rifle cleaned always , ;thinking maybe carbon ring build up but Factory Ammo - No problem. So what do you think is wrong or an I missing something . This is the only Weatherby rd I reload , others are standard cartridges. Thank you Don

 

[JimP]

I'd start with trying another powder, perhaps some RL 17 if you can find it.

A sticking bolt is a sign of excessive pressure or a chamber problem. But if factory rounds shoot fine then I'd suspect pressure.

 

[PARA45]

What you are trying to do is very difficult. First, the powder blend that Weatherby (Norma) uses for their load is not available to the public. I believe your rifle is letting you know that you have reached max pressure. I'm a huge Weatherby fan, and have many Weatherby cartridges, and reload for most of them. I however, do not go for max velocity, I let my rifle tell me what she likes, and if my load is 100-200 fps slower than what a factory load is, and it's accurate, I stick with it. I don't believe an animal will know the difference between getting shot with a bullet going at 3300 fps, vs. 3500 fps.

Here is something else you may want to try, and this is what I do with my Weatherby cartridges. If these cases have been fired on my rifles, I neck size the case, and I chamber check every single case. After about 3-4 firings, I full length resize, and trim. Have you check to see how your resized cases fit in the chamber?

I hope this helps.

 

[uplander01]

Odd. Has it ever been sticky before?

Wipe Out is the only cleaner I would trust to try and eliminate all the carbon from teh neck of the chamber,...that would be worth a try. Do not use regular cleaner and any sort of chamber brush, you'll score the chamber.

 

[Ruraldoc]

It is very at times to match Weatherby factory velocities with hand loads.

Weatherby( Norma) uses special blends of powder that are not available to hand loaders.

I always had best results using Reloader 22 which is close to Norma MRP.

 

[Don458]

What you are trying to do is very difficult. First, the powder blend that Weatherby (Norma) uses for their load is not available to the public. I believe your rifle is letting you know that you have reached max pressure. I'm a huge Weatherby fan, and have many Weatherby cartridges, and reload for most of them. I however, do not go for max velocity, I let my rifle tell me what she likes, and if my load is 100-200 fps slower than what a factory load is, and it's accurate, I stick with it. I don't believe an animal will know the difference between getting shot with a bullet going at 3300 fps, vs. 3500 fps.

Here is something else you may want to try, and this is what I do with my Weatherby cartridges. If these cases have been fired on my rifles, I neck size the case, and I chamber check every single case. After about 3-4 firings, I full length resize, and trim. Have you check to see how your resized cases fit in the chamber?

I hope this helps.

Yes all sized cartridges were chambered in rifle very easily, My Die are Hornady Full length New dimensions I failed to add. And im using the Federal LR match grade primers. Like I was saying even the loads 47.5 up still sticking bolt. I may try the what you suggested with the neck sizing. I just love the tsz @ 3500 fps what it does to game. I have plenty of the Factory loaded 100 gr hornady BTSp.

 

[uplander01]

Is it a Weatherby rifle?

 

[Don458]

Is it a Weatherby rifle?

Mark V Accumark.

 

[JimP]

One other thing, did you chronograph the speed of the factory round?

If not, factory velocities are arrived at using a test barrel which is quit different than a actual rifle. That along with most post a higher velocity than it really is.

When I built my load for my .340 Weatherby I sent a number of factory rounds over the chronograph and then selected a powder, that one wasn't doing what I wanted so I switched to RL22 where the max load was above what I was getting with the factory rounds. Backed it down to the factory velocity and I have a great reloaded round that is quite a ways below the max for that powder with lower pressures.

 

[Don458]

One other thing, did you chronograph the speed of the factory round?

If not, factory velocities are arrived at using a test barrel which is quit different than a actual rifle. That along with most post a higher velocity than it really is.

When I built my load for my .340 Weatherby I sent a number of factory rounds over the chronograph and then selected a powder, that one wasn't doing what I wanted so I switched to RL22 where the max load was above what I was getting with the factory rounds. Backed it down to the factory velocity and I have a great reloaded round that is quite a ways below the max for that powder with lower pressures.

Yes. All as stated 3500 I will try reloder 17. If I can find it. At the time IMR 4350 was all that was available.

 

[uplander01]

Mark V Accumark.

I would make sure the bolt lugs have a light coating of slick grease on them, also put a little grease on the bolt body by the bolt handle where it engages in the action body. This can help a lot on weatherby actions, if these areas get dry you may just be experiencing action binding.

.....but on the previous comment, the rifle will tell you when pressures are too high, but going down 200 fps I would have thought things would have gotten easier....

 

[Jefferry404]

thanks for the question and data as I like real world info to input to my reloading data.
I started with Hodgdon load data for the 25-06 and 85gn ttsx (almost same case capacity as the 240wby and all copper bullet) with IMR4350 and using Quickload, fit the powder to the velocity and pressure. Barnes data uses Norma cases and then used the Norma manual case capacity for the 240wby.
Doing this shows:
Barnes manual for 85gn tsx, 50.0gn imr4350, 24" barrel has 3506fps.
Quickload for the Barnes parameters has 3457fps and 64660 psi.
This is the max load from Barnes and the QL pressure is at the high end with a bit less velocity, a reasonable correlation.

Then QL for your 48gn and 24" barrel is 3333fps and 57.4kpsi and hard to see this would have
sticky bolt lift as well, so not clear where that is coming from (although the 50.0gn is 1.3% above CIP max average pressure) but well below the PK level 73389psi). Perhaps the rifle was stressed with the hot load?
Steve