Cant Match Weatherby Ammo Velocity??

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JasonYuke

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Well after all the internet searches, and I confirmed my own finings with my 300 Wby 700 rem?
Just cany match factory ammo with 165 gr or 180 bullets.
I have tried everything over the last 4 months, different powders, bullets, not worried about cloverleafing groups, I just tried to match the weatherby factory velocity , out of my 700 26" barrel.

My findings, and trust me i pushed the pressure limits, safe, but pushed them far above the reccomended data!( dont do it, i went slow!).
But after so much powder it would just not fly any faster.
At least 100-150 bellow theres??
Any one find the same?
 
are you comparing your loads to weatherby ammo chrony'd in your rifle? or their factory ammo specs from a test rifle...

3250 f/s with a 180 is more like 300 Ultra performance. 3100 f/s is about as hard as a 300 win mag will push a 180. Maybe you just have a 'slow' barrel
 
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When I fired weatherby factory loads in my mark Vs(257wby and 300wby),there were extrusion marks on the brass and the case head expansion was beyond acceptable limits,both of which indicate excessive pressure.I am not willing to load to levels where pressure signs are evident,so my handloads produced slightly less velocity than the factory loads.
 
Tod I am pushing out 3160 Fps with 165s and 3075 with 180s,
The chrony showed on 2 shots with 180s, factory ammo that was given to me by a buddy 3185 (180s) and he told me that the factory ammo for weatherby 165s was close to 3300 fps that he shot with a different rifle but the same chrony.
Perhapps i do have a slow barrel!
The wierd thing is (not to worried because I have plenty snap anyway) is that loads suggester in all the mannuals show Velocity close to factory ammo however like mentioned( I am over) but still way under what the mannuals suggest, rulled out reloading errors, ie scaled and powders, there all in line.

I guess it really does not matter the velocity for me the 700 still shoots straight.
As you mentioned with the 300 win mags yes thats what i am finding out of my other 700 win mag I am around the velocity you suggested!

I do find that some suggest hioghr velocities than you can achieve! I find that with my 30-378 as well its about 150-200 feet lower than what weatherby suggested??
 
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well chalk it up to having a 'slow' barrel. If it shoots straight and will push a good 180 at over three grand, you should be alright for anything you stumble across in Canada, let alone Ontario :D although I hear they have some pretty big whitetail fawns there :D
 
I heard this was a thing with Lazzeroni rifles and ammunition. From what I've gathered they'd use longer barrels, sight in higher, and test fire in high mountain areas where the air was thinner.

Do you suspect we're facing a similar sort of 'weight loss game?' If so I'm really not surprised.

- Dave.
 
and do not forget that factories are all using blended powders now as well, powders that are not available to the public and are made specific for certain manufacturers.

makes a huge difference.... take a look at factory 270wsm ammo, then look at the loading manual, according to the loading manuals I have even getting to factory velocities is a bit of a stretch.
 
Westicle said:
and do not forget that factories are all using blended powders now as well, powders that are not available to the public and are made specific for certain manufacturers.

QUOTE]

At one time weatherby used a blend of norma powders. Kinda like thw kernals 11 different herbs and spices
Click to expand...
 
Most likely problem is you dont have a factory Wby MKV . Most MkVs have a insane amount of freebore , which gives the bullet a pretty good start before bullet hits rifling ( which helps reduce max pressures, or allows higher powder charge with same max pressure )

I have a 257Wby MKV . My buddy chambered a 257Wby using a Cylmer reamer. It does not have as much freebore . My loads will loosen primers in his rifle and not mine ( primers actually fell out ! )

Friend has a 30-378 that he had the barrel set back and rechambered to take the freebore out. Had to work out new loads because pressure went way to high after this modification

Wby and load books like the Hornady and Speer also list the Wby MKV as the test gun. Speer manual has a warning discussing using their data in non Wby chambered rifles

In addition, Norma loaded Wby ammo is notoriously hot . Having said that, I have no problems reaching factory velocities with my handloads for 257Wby and 30-378Wby

Lastly I hope you are using Norma / Wby brass. The non Norma brass is often much softer. The worst of the non Norma is the Federal Wby brass ( they quite making it ).
 
My .300Wby was getting 3250fps with 180gr Hornady SP out of a Lazermark. This was reloads, and not showing any pressure signs. I was also getting 3350fps out of my .270Wby in a Vanguard 24" barrel for a 130gr BT. Got pressure signs at 3450fps with the same bullet.

Never had any problems getting published velocities from any Weatherby's so far. Still have to chrono my .257 and .378 ;)
 
At one time Clymer and most other manufacturers made all their Wby. reamers with built in freebore equal to Wby. standards. That may very well not be the case today. Another major factor is the amount of use the reamer has had. A new one will cut a maximum chamber (better) and a well used one will cut a minimum or close to minimum chamber (way worse).
Combine the two and we have a Wby. custom rifle that is near worthless in terms of reaching the potential of the cartridge. There are 4 good ones in the family: Two Sako 995's in 30-378, one MkV 378, and one custom 300 cut with a new reamer and throated. All have been in use for many years, and all can meet or exceed published velocities, and all have 26" bbls.
One comment that I cannot resist for the hi-vel critics: It's perfectly true that a 30-06 handled properly will kill any game animal found in North America. So will many other "lesser" cartridges. The difference is that a few hundred fps of velocity can make the difference between an animal dropping in it's tracks and on one walking, staggering, or running off to die somewhere else. Been there, done that, or seen that with every species in BC except goat and grizz. It's quite impressive for the uninitiated to see a whackin' great moose shot through the brisket with a little 165 gr Partition simply turn turtle in it's tracks with the only sign of life being one hind leg giving two or three twitches. That's about three feet of penetration through hide, meat, grisle and bone before rupturing every blood vessel in the boiler room.
 
300 WBYs should do 3250-3300 fps with 180s. Ive had several and all would do it without pressure problems. If yours won't do it with 7828 you have a slow barrel, however as Tod said anything over 3000 should work fairly well.
 
Jason,
Just for a little more input, I have a Model 70 Classic 300 Weatherby with a 26" bbl. At the risk of being called a liar (or worse), this rifle shoots factory Weatherby brand 165 gr. loads at 3450 fps, and these are very accurate as well. Have never had any indications of undue pressure.

I made an attempt to handload for this rifle, but wasn't getting within 200 fps of the factory loads, so, oh, what the heck, guess I'll just shoot factory's!
 
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