.257 wthby problem...
i recentlyhad a 257 wthby conversion on a lh rem 700 (previously 7mm). the action was trued and lugs lapped. I used a douglas premium bbl. 26 in pipe w a 11degree crown.
Here is the problem. The gun shot great, less than moa. the problem is case expansion. I used both factory loads and reloads, the reloads were new federal brass trimmed to length, fed mag primer 62 grains of imr 4831 and nosler 120 grain partion bullets. the case expansion was aprox .004. the cases were very difficult to extract. It did this with both brass and nickel cases.
After this was discovered the reamer was checked and the dimensions were within limits. headspace was confirmed again, and casting was made and found to be ok. another barrel was installed and the same problem persisted.
Does anyone kow the extent of the length of freebore that wthby uses in factory rifles? Any other thoughts of expansion other than
freebore? I know that the load is not excessive and I do not think that the factory ammo would be either. any thoughts or comments would be greatly appreciated before I try another barrel from a different manfacture. thanks.
If guns cause crime, all mine are defective.
Here is the problem. The gun shot great, less than moa. the problem is case expansion. I used both factory loads and reloads, the reloads were new federal brass trimmed to length, fed mag primer 62 grains of imr 4831 and nosler 120 grain partion bullets. the case expansion was aprox .004. the cases were very difficult to extract. It did this with both brass and nickel cases.
After this was discovered the reamer was checked and the dimensions were within limits. headspace was confirmed again, and casting was made and found to be ok. another barrel was installed and the same problem persisted.
Does anyone kow the extent of the length of freebore that wthby uses in factory rifles? Any other thoughts of expansion other than
freebore? I know that the load is not excessive and I do not think that the factory ammo would be either. any thoughts or comments would be greatly appreciated before I try another barrel from a different manfacture. thanks.
If guns cause crime, all mine are defective.
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i recentlyhad a 257 wthby conversion on a lh rem 700 (previously 7mm). the action was trued and lugs lapped. I used a douglas premium bbl. 26 in pipe w a 11degree crown.
Here is the problem. The gun shot great, less than moa. the problem is case expansion. I used both factory loads and reloads, the reloads were new federal brass trimmed to length, fed mag primer 62 grains of imr 4831 and nosler 120 grain partion bullets. the case expansion was aprox .004. the cases were very difficult to extract. It did this with both brass and nickel cases.
After this was discovered the reamer was checked and the dimensions were within limits. headspace was confirmed again, and casting was made and found to be ok. another barrel was installed and the same problem persisted.
Does anyone kow the extent of the length of freebore that wthby uses in factory rifles? Any other thoughts of expansion other than
freebore? I know that the load is not excessive and I do not think that the factory ammo would be either. any thoughts or comments would be greatly appreciated before I try another barrel from a different manfacture. thanks.
If guns cause crime, all mine are defective.0 -
My 2 cents
If you used the same reamer to set up the chamber, I would look deeper into the fact this may be the problem. After setting up the chamber, Was the chamber polished real well ? Weatherby cases are senseable in the area where the neck is, The case on the neck is rounded unlike conventional cases, This could be the area giving you the problem. If you try a hand-load try polishing your cases real shiney, Then shoot 3 or so rounds off and when you get the cases out of the chamber look at them real close under a magnafieing glass with a light and inspect the cases looking for the area that is causing the problem. Also try trimming a few cases shorter and see if this helps. Check the neck area close. You may want to set the barrel back a few thousands and try a different reamer.
Note: Even a new reamer could be at fault !
Robert
Edited by - hotrodusa on 08/17/2002 22:57:330 -
Was bolt lift hard or just cases being hard to extract. I had a 416 Taylor that would have good bolt lift but the cases were still hard to exract, The problem was caused by a chamber ring. Or a slight bulge in the chamber. I use .005 as the max for case expansion over factory rounds.
AlleninAlaska
He who dares not offend cannot be honest.
-- Thomas Paine0 -
Checking case, and neck diameter runout at different spots.
If not in spec, bolt,and/or receiver are not in aligned with bore center.
Reamer/barrel set up in lathe is not centered or in linear alignment.
Also try different brass. Would not be the first time brass was bad.
Freebore isn't causing it.
Happy Bullet Holes!0 -
All great thoughts!! Thank you gents. Sometimes one needs outside input to put them back on track. ill let you all know what works out.
If guns cause crime, all mine are defective.0 -
I can tell you that the wby line of cartridges don't allow musch room for error in chamber or throat dimensions. I blew a 1917 Enfield action to pieces with a starting load a few years ago because the chamber was tight and the throat was short.
Mobuck0 -
The chamber should be polished bright, the fired case taper and chamber cast taper should be per spec and maybe most importantly,
the freebore and chamber throating should be per Weatherby specifications. Weatherby freeboring was necessary to obtain the higher velocities within safe pressures.0 -
Do you happen to know the amount of freebore that wthby uses? this question is the hardest to find the awnser. I cant find a legit source to provide an adequate awnser.
If guns cause crime, all mine are defective.0 -
I would call Clymer Reamer Co on Weatherby throating and freeboring details. Also give them your measurements of fired brass and chamber castings. Your chamber casts should include the freebore and throat. 0 -
Thanks Ill do that.
If guns cause crime, all mine are defective.0 -
Hi, sounds like you and I have the same tast in rifles. I built my 257 Weatherby on a Remington 700 BDL action put a Douglas Premium match barrel on it and placed the barrled action in a Remington Sendero stock. I use Federal brass, Fedral match primers, 120gr nosler partition bullets, 59gr of IMR 4350. This is the max load according to the Nosler Hand loading manuel. My rifle will shoot a 5 shot group that you can cover with a nickle at 100 yards . Try reducing your load and try another powder. You may be over pressuring the action and causeing the cases to grow to much. The Weatherby factory loads and Remington factory loads did have more recoil than my hand loads so I belive they were loaded a little heaver than my hand loads. But even though my reloads shoot right at 3100 FPS they are more accurait than the factory loads. 200 FPS is not that big of a differance when you can put a bullet in the vital area of a deer or antalop out to 3-500 yards. I also did not free bore my rifle. I made a dummy round and set the bullet back so it was only a few 1000's off the lands. I hope I have helped, shoot straight, make one shot kills, God Bless. 0
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