need help with a 6.5 X300 weatherby

[fatbastard]

I have been having a problem with this gun.
I have been working up loads for this gun but I keep blowing the bolt and needing to hammer it out every time.
Any ideas why this is happening?
any one have a load for this that works.

Help please

I have had the head space done.
and still the same problem

Don

 

[cdnredneck_t3]

We need some more info. What bullet, powder and charge weight are you using?

 

[Wookie316]

Slow powder will be your friend. My 6.5mm-300 Win Mag likes H870. I can go up to 80gr H870 with a 140gr bullet in that case & still be fine. I suspect you could go 2-3gr higher with a WBY case. US869 should work very well in that setup too since H870 is extinct

 

[fatbastard]

HI..The old load was H870 84g with 140g bullet(3050 ft per sec.). The gun will not open now with that load. Bolt will come up but you need a cleaning rod to get the brass out. Drop the load by 5% till I was down to 68.4g and velocity was to slow for me 2896 and brass still would not extract. The Head space was excessive (.015 to Long) had it corrected. The problem still exists. Have tried H5010 and WC 867 all to no avail.

 

[Pathfinder]

HI..The old load was H870 84g with 140g bullet(3050 ft per sec.). The gun will not open now with that load. Bolt will come up but you need a cleaning rod to get the brass out. Drop the load by 5% till I was down to 68.4g and velocity was to slow for me 2896 and brass still would not extract. The Head space was excessive (.015 to Long) had it corrected. The problem still exists. Have tried H5010 and WC 867 all to no avail.

Are you able to seat the bullets out at all, how is the throat. This reminds me of issues with the old 264 win mags with the short throats.

 

[Andy]

HI..The old load was H870 84g with 140g bullet(3050 ft per sec.). The gun will not open now with that load. Bolt will come up but you need a cleaning rod to get the brass out. Drop the load by 5% till I was down to 68.4g and velocity was to slow for me 2896 and brass still would not extract. The Head space was excessive (.015 to Long) had it corrected. The problem still exists. Have tried H5010 and WC 867 all to no avail.

It's not overpressure then. Is the brass all scratched when it is extracted?

 

[Wookie316]

What action is this built on? Any photos or measurments on the brass? What length & twist are the barrel?

 

[downwindtracker2]

Something outside of the load is happening. Is it really H-870? or is the barrel really a 6mm? 2900 is 270 territory.

 

[fatbastard]

Bullets are not seated out, over .250 jump. Just had a thread taken off and head space corrected. Brass not all scratched when it is extracted. In fact looks good. Browning Mouser 98. Twist 1 in 9. maybe 1in 8. Brass web new .505 fired .513. The throat is not great. the barrel is 27 in.

 

[Pathfinder]

strange....try seating your bullet 5-10 thou away from the lands to create more powder space/decompressing your load. Might help with the pressure.

 

[Why not?]

I'll bet that if you clean the chamber really well, that problem will go away.

I have seen this same problem in a 7X57 Husqvarna and a 222 SAKO. Both had very lightly rusted chambers, and were fixed up in a jiff with some 000 steel wool and oil on a brass rod in a hand drill.

Ted

 

[Wookie316]

I've always had new brass measure .512 at the expansion ring? .505 does not seem right?
But if you are .513 after firing, you should be fine as I have had cases come out no problem up to .515 from most of my belted magnums.
Is it perhaps an actual mechanical issue with the extractor itself that is causing this?

 

[dan belisle]

When the headspace was corrected was the chamber recut correctly? Wby's (and in particularly this wildcat version) have pretty long throats and leades. Perhaps this was unintentionally shortened by the head space correction. - dan

 

[timmy204]

How about neck clearance, maybe your necks are to thick. Measure your neck of a round with bullet seated, then measure neck of fired case. Should be at least .002 difference.Are your cases trimmed to right length? Good luck with it.

 

[Eagleye]

The 6.5 - 300 Whby is poison on throats. How many rounds through this one? If over 500 total, the throat may be getting very rough, which will increase pressures significantly. Worth a look with a borescope. Eagleye.

 

[oh_j0ker]

H870 and Carbon Buildup

Hi,
I have been doing a fair amount of reading in trying to find a load for my 6.5X300 Winchester Mag. In that research it is really apparent that the H870 powder creates a carbon ring that will provide all of the symptoms that you mention. The writers indicate that the carbon ring will not come out with normal barrel cleaners and suggest using Bon Ami. They indicate this ring develops after about 10 shots.
Regards,
Rick