Is it excessive pressure?

M

marion packett

Guest
On my remington action 6.5-284 I get an easy bolt lift for the first half, then it wants to stop and the remaining lift is hard.Is this excessive pressure or could it be something else? I thought if it i too much pressure it would be evident in the beginning of bolt lift. Your comments will be appreciated. Thanks,Marion
 
could be, but I really don't understand bolt timimg. I looked at the video and will research further.
 
When you first unlock the bolt (lift it), you are not using any of the camming on the action. The cam comes in to play for the extraction of the case from the chamber.

When you true an action, you are removing metal from the rear of bolt lugs and from the action itself, to square things up. This removing of metal causes the bolt body and handle to move rearward, away from the cam on the action. If you are too far away, you have next to nil for camming to extract the case.

Close you bolt and measure the distance between the bolt handle and the action cut out. You want the handle close to the front of the cut out, not the rear. Stan explains this in one of the videos...

K
 
It also can be

A soft brass/excessive pressure combination. When the bolt comes to the point when the extractor starts to move the case back (via the camming action) the case my be "too sticky" to the chamber wall.

Oil 2-3 cases slightly and/or reduce the load in 2-3 loads or use a different brass to determine the problem. If there is no change, than it may be the camming timming of the bolt.

Shoot better
Peter
 
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Marion,

You state that "half way up" the bolt gets sticky............

I feel that you need the opinion of a gunsmith or that you need to really look at the contact area at the root of the bolt where the extraction cam is located. Watch carefully as you roll the bolt open, look into the groove in front of the bolt handle and see.....does the tightness occur when the cam surfaces meet?

If so, it's typical "difficult extraction" due to pressure.

If it gets tight BEFORE the camming surfaces meet then you should get it checked out I think.

al
 
Likely you have either excessive pressure, or tired brass, or not-quite-rightly resized brass.

If you follow the tests recommended by PPP MMM, you'll discover which.

BTW
Close you bolt and measure the distance between the bolt handle and the action cut out. You want the handle close to the front of the cut out, not the rear.
Click to expand...
isn't quite right. You should measure the clearance not when the bolt is fully closed, and against the bolt cutout in the receiver, but between the surfaces just before the cam engages. There is no reason to assume the cut in the receiver is 90-degrees.

How do I know this? Ah, experience. I have an earlier 700, serial number XX,XXX. The cut for the bolt handle recess in the receiver is just a bit forward of the cut before the cam engages. When the bolt is fully seated, the handle-receiver measures .020. With the same "timing," it measures only .010 just before the cam. Prettier that way, I suppose.

So if you measure at the receiver cut and "move the bolt handle forward" .010, the bolt will no longer close. You can in effect "move the bolt handle forward" if you are replacing a Remington bolt head with a Savage bolt head, BTW. It's not fun when the bolt won't close -- Wound up taking the same .010 off the lugs that I had added when placing the bolt head.

Anyway, I doubt this is your problem, but if you are going to check it, be sure to measure at the right place.
 
It is probably a bolt face that is not square. The extraction cam is at the top quarter of bolt lift and easy to see when things meet. With excess pressure and brass flow into ejector hole bolt lift is immediately hard. With slightly untrue face and everything else square you would feel resistance half way up.
BV
 
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