.284 bolt problem

[TAJ45]

I just read HenryP's (Henry Pasquet) info via interview here on his 2013 1000 yd National win.

In this he mentions the reason for his Shehane chamber choice being very hard bolt closing on a std .284Win chamber. Coincidentally, I recently felt the very same thing when dry firing a successful national competitor's rig at a clinic.

Why? I do not have a Shehane print for comparison but am having a difficult time understanding why physical cartridge dimensions would make a difference on a properly spec'd and smithed gun. Anyone? No, I haven't pm'd Henry - yet. But from the tenor of the interview, I think it would be an enjoyable confab/learning experience.

 

[Tommie]

Straighter (less angle) body walls exert less thrust against the bolt. Usually doesn't become an issue until pressures get pushed near max. It's the reason Ackley Improved cartridges tend to extract effortlessly even when pressures approach the scary zone.

 

[Dave L Kiff]

I just read HenryP's (Henry Pasquet) info via interview here on his 2013 1000 yd National win.

In this he mentions the reason for his Shehane chamber choice being very hard bolt closing on a std .284Win chamber. Coincidentally, I recently felt the very same thing when dry firing a successful national competitor's rig at a clinic.

Why? I do not have a Shehane print for comparison but am having a difficult time understanding why physical cartridge dimensions would make a difference on a properly spec'd and smithed gun. Anyone? No, I haven't pm'd Henry - yet. But from the tenor of the interview, I think it would be an enjoyable confab/learning experience.

I ground the reamer for that and have information for you, thanks Dave

 

[TAJ45]

Straighter (less angle) body walls exert less thrust against the bolt. Usually doesn't become an issue until pressures get pushed near max. It's the reason Ackley Improved cartridges tend to extract effortlessly even when pressures approach the scary zone.

Does this have anything to do with closing the bolt on an Empty chamber?

 

[LRPV]

Q: Some people say the .284 Shehane is not as accurate as the straight .284 Winchester. You’ve proved them wrong. Why do you like the .284 Shehane? More speed, less pressure?

Henry: The reason I rechambered my 7mm barrels to .284 Shehane was not velocity, pressure, or brass life. It was all about bolt lift. My straight .284 almost required me to stand up to eject brass. I damaged an extractor and had to send the bolt back to BAT. With the .284 Shehane, my bolt cycles like there is no case to eject.

Unless there is another article out there that describes closing the bolt, the "problem" was with bolt lift not closing.

 

[TAJ45]

Q: Some people say the .284 Shehane is not as accurate as the straight .284 Winchester. You’ve proved them wrong. Why do you like the .284 Shehane? More speed, less pressure?

Henry: The reason I rechambered my 7mm barrels to .284 Shehane was not velocity, pressure, or brass life. It was all about bolt lift. My straight .284 almost required me to stand up to eject brass. I damaged an extractor and had to send the bolt back to BAT. With the .284 Shehane, my bolt cycles like there is no case to eject.

Unless there is another article out there that describes closing the bolt, the "problem" was with bolt lift not closing.

You are so right.....A bit red in the face here.

Now for a follow up Q: Would it be less taper on the Shehane that would allow that much of a redux in bolt lift force needed?
Upon mental review, it was difficult to both close AND open on the empty chamber. I hope he would not have overlooked lubing it after the last cleaning.

 

[LRPV]

Not all actions are equal. I've ran some BAT actions that require more or less effort working the bolt. I don't know if it's the way they are set up or just differences between individual actions. The two BAT's that I have left are very smooth and easy to manipulate no matter what. Mr. Kiff replied to your thread and offered to talk to you about it, so you might take him up on the offer. Henry and I use the same gunsmith and last year when I had a 284 Shehane chambered up for my HG it was my understanding that the same reamer was used for my barrel. After fireforming and working up a Shehane powder charge, I had clicky bolt lift shooting the larger charge of powder. I went back and increased my fireforming load by .6 of a grain and shot the same velocity as I did while fireforming without issues. I was using 284 Norma brass instead of Lapua which could've been the reason for the clicky bolt. I haven't been back to try to figure out the issue yet. Brass size, chamber size and die size all need to work together to insure everything works as it should. The first sizing die that I tried to use was not sizing the base of the case at all and this can cause the stiffer/clicky bolt lift from experience with other calibers.

 

[hpasquet]

I bumped the neck on the straight 284 so that the bolt closed easily. It was still hard to eject the brass. Previous comments are correct on the reduced taper. I ran the same loads and velocity on the straight and the Shehane. The Shehane brass ejected like a 22 rimfire, allowing faster shooting. The prize is for accuracy, NOT velocity. My current lot number of Berger bullets is not as good as the one I used in 2013. I try to share all I know to get as many shooters doing as well as possible in the least time for the least cost. I am glad to answer any questions.
Henry

 

[TAJ45]

Not all actions are equal. I've ran some BAT actions that require more or less effort working the bolt. I don't know if it's the way they are set up or just differences between individual actions. The two BAT's that I have left are very smooth and easy to manipulate no matter what. Mr. Kiff replied to your thread and offered to talk to you about it, so you might take him up on the offer. Henry and I use the same gunsmith and last year when I had a 284 Shehane chambered up for my HG it was my understanding that the same reamer was used for my barrel. After fireforming and working up a Shehane powder charge, I had clicky bolt lift shooting the larger charge of powder. I went back and increased my fireforming load by .6 of a grain and shot the same velocity as I did while fireforming without issues. I was using 284 Norma brass instead of Lapua which could've been the reason for the clicky bolt. I haven't been back to try to figure out the issue yet. Brass size, chamber size and die size all need to work together to insure everything works as it should. The first sizing die that I tried to use was not sizing the base of the case at all and this can cause the stiffer/clicky bolt lift from experience with other calibers.

Interesting bend this thread is evolving to. Yessir, I indeed PM'd Mr. Dave after his generous offer to share time and background knowledge. My bud schooled me on the click - for sure, all sizing dies are not created equally. It seems for our app, the older RCBS 22-250 will size the bases a bit more than current.....which is helping on our XC creation.
Longer neck and body, keeping the 30° for now, shooting for a shorter .243 case but burying the turbulence point. When I was working the bolt on his rig, I couldn't believe the resistance I encountered. Gun's owner said Ireland was something else last summer......shooting over a peat bog. Mirage was past wicked.

Mr. Pasquet, do you give personal trainer lessons ? I have a trip West on my recurring bucket list and could well swing into MT one of these days on my way to see Sherm at X Cal. Bought a bbl from him - private transaction. I NEED to get into a colony shoot before I mothball my reloading equipment.
Many thanks for the replies, shared knowledge and general help.
Tom NRA
Life '76

 

[hpasquet]

Glad to help anyone any time with any thing. We can shoot 300 off the deck or 1000 down the runway. My wife's doctor came by two weeks ago and got a 3 shot 4" group in the wind with his first ever shots at 1000. We went over reloading also. I will soon be 75 so why not help the next generation? I am in SE Mo.