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Heavy bolt lift

I would be looking at either neck clearance. take fired case a see if a bullet will slide freely into it, also look at over all case length, if its a short chamber you could be crushing the neck into the throat and having to pull it out. if you have a bore scope chamber spent case and look at the end of the case in the chamber and see if its bottomed out.
 
It seems to me that factory loads these days ARE hot. Ever since they all started putting velocity stats on the box, and competing with each other in that department, I'd be surprised if I DIDN'T get a tight bolt lift.

And tight bolt lift is kinda subjective to boot. If you have to take the rifle off the bags, grip it tightly with one hand and devote the other to simply lifting the bolt -- that's way too tight. If you can leave it on the bags, and lift it with one or two fingers, and it just feels kinda tight, I'd call that pretty normal for a factory rifle and hunting load.

Also don't forget that for a lot of the "newer" cartridges, the ammo makers know that the rifles are modern, strong actions with great steel and tech which would allow tremendous pressure before hitting the danger zone.

I kind of like a little bit of "tight bolt" because it tells me where to set my sizer die, as well as my powder charge. Other signs we need to watch for are extremely flat and /or cratered primers, and ejector swipe marks. Add a chronograph to your tools and there's no reason to have much worry about this. jd
 
It seems to me that factory loads these days ARE hot. Ever since they all started putting velocity stats on the box, and competing with each other in that department, I'd be surprised if I DIDN'T get a tight bolt lift.

And tight bolt lift is kinda subjective to boot. If you have to take the rifle off the bags, grip it tightly with one hand and devote the other to simply lifting the bolt -- that's way too tight. If you can leave it on the bags, and lift it with one or two fingers, and it just feels kinda tight, I'd call that pretty normal for a factory rifle and hunting load.

Also don't forget that for a lot of the "newer" cartridges, the ammo makers know that the rifles are modern, strong actions with great steel and tech which would allow tremendous pressure before hitting the danger zone.

I kind of like a little bit of "tight bolt" because it tells me where to set my sizer die, as well as my powder charge. Other signs we need to watch for are extremely flat and /or cratered primers, and ejector swipe marks. Add a chronograph to your tools and there's no reason to have much worry about this. jd
I cannot remember but is the op using any lube on the bolt lugs and primary extraction cam.

Uncle Bruce
 
It seems to me that factory loads these days ARE hot. Ever since they all started putting velocity stats on the box, and competing with each other in that department, I'd be surprised if I DIDN'T get a tight bolt lift.

And tight bolt lift is kinda subjective to boot. If you have to take the rifle off the bags, grip it tightly with one hand and devote the other to simply lifting the bolt -- that's way too tight. If you can leave it on the bags, and lift it with one or two fingers, and it just feels kinda tight, I'd call that pretty normal for a factory rifle and hunting load.

Also don't forget that for a lot of the "newer" cartridges, the ammo makers know that the rifles are modern, strong actions with great steel and tech which would allow tremendous pressure before hitting the danger zone.

I kind of like a little bit of "tight bolt" because it tells me where to set my sizer die, as well as my powder charge. Other signs we need to watch for are extremely flat and /or cratered primers, and ejector swipe marks. Add a chronograph to your tools and there's no reason to have much worry about this. jd
This is standing up, holding the rifle down and pulling up hard on the bolt to lift it bolt lift.
 
I would be looking at either neck clearance. take fired case a see if a bullet will slide freely into it, also look at over all case length, if its a short chamber you could be crushing the neck into the throat and having to pull it out. if you have a bore scope chamber spent case and look at the end of the case in the chamber and see if its bottomed out.
I took a fired case, dropped a 143gr ELDX down the neck- went all the wat down no problemo. And-the case isn't growing-it's expanding-width wise.
 
But the title said "Heavy bolt lift" This IS a pressure sign.

Whan happens if you drop rhe powder charge 1 grain?
I don't know- I have already established that the cases have expanded after firing at both the case web and immediately below the shoulder. I'm starting to lean more towards an improper chamber-too big.
 
I cannot remember but is the op using any lube on the bolt lugs and primary extraction cam.

Uncle Bruce
Yes I am-I'm going to the range once more with factory Hornady Precision Hunter ammo. The bolt lugs are lubed and the extraction cam at the bolt shroud will be greased. I will say-I've never had to grease a cam in all my other rifles, and I've never had the hard bolt lift in them either-this is a new one too me!-
 
I've applied red gun grease and checked the backside of the bolt lugs once the bolt was closed and opened-there are no signs of the grease rubbing on the back side. There was good contact on the tops and bottoms/sides of the lugs.
End of the bolt fits a recess in the barrel, if not properly aligned or sized correctly. The bolt can make contact, this can result in a harder to open bolt after firing.
 
From what I'm able to tell-using grease-it appears fine.
The small particles of brass you see may be from the extractor trying to pull a tight case out of the chamber and slipping out of the exractor groove. Put some magic marker on the extractor groove.

On my old Rem 700 I could count how many times a case was fired by counting the extractor nicks on the case rims.
 
Don't flame me but I have a question on oversize chamber problems. I am thinking if the chamber is still tapered to be smaller in the font than the rear regardless of being out of SAMMI spec and all other things being equal it should still extract with the same amount of force as a in spec chamber. The 6.5 CM SAMMI chamber shape is tapered from .4741 at the .200 line to .4630 right at the shoulder to case junction. If the chamber is reamed oversized compared to SAMMI spec unless there is larger diameter pocket in the middle of the chamber somewhere creating a blowen out or wider portion not keeping the proper taper, Shouldn't it in theory still have the typical bolt lift and extraction force?
 
The small particles of brass you see may be from the extractor trying to pull a tight case out of the chamber and slipping out of the exractor groove. Put some magic marker on the extractor groove.

On my old Rem 700 I could count how many times a case was fired by counting the extractor nicks on the case rims.
The brass I'm referring to is on the bolt face and common sense would tell me that the case is pushed so tight against the bolt face that the brass is actually rubbing off and sticking to the bolt face. I have to clean it with copper remover.
 
My Howa 6.5 Creedmoor gave slightly hard bolt lift from new with factory Hornady 140 Grain ELD-M Match ammo. When I started hand loading with SAKO brass and the same bullet with AR2209 (H4350) I started low at 38.5gr and ran into slightly hard extraction at 40gr and only 2600fps. I loaded up 50 rounds at 39.5gr and fired them off at 600m over a few sessions. 1/2 MOA accuracy but only 2580 fps. SD was 12 so not too bad.

I've since been able to work up to 40.5gr and 2650 fps with no pressure signs as the barrel broke in. Shoots fine out to 900m (984 yards) but accuracy dropped off at 1000m (1094 yards) due to what I expect is transonic instability. Just going a bit too slow. Not terrible accuracy but not as good as 900m with the odd flyer into the 8 ring.

So I suspect the barrels on the Howas are just a bit slow and hit max pressure at lower charges. I'm going to see if I can get a bit more velocity with Hornady brass. I'd like to get 2750fps but I doubt I will.
At an MV of 2650, you will not be transonic at 1100 yds - in fact you should be over 1200fps. Your load of 40.5 is about right - I would ditch the Hornady bullet - try Lapua 139 ( I like this one) or Berger/ Sierra 142g Sako Creedmoor brass is excellent and seems to have gone from the market in NZ, which is a pain for those that use it.
 
At an MV of 2650, you will not be transonic at 1100 yds - in fact you should be over 1200fps. Your load of 40.5 is about right - I would ditch the Hornady bullet - try Lapua 139 ( I like this one) or Berger/ Sierra 142g Sako Creedmoor brass is excellent and seems to have gone from the market in NZ, which is a pain for those that use it.
1200 - 1240 fps depending on environment. That's in the transonic zone though which is around mach 0.8 - 1.2.

Agree on the Hornady but I've got 600 of them left and rather than use one bullet for out to 700m and then another for 800-1000m I was planning on just using them up. Out to 700m they shoot really well. Would you suggest running another bullet just for the longer ranges?

Plenty of Sako brass here in Oz. No doubt there would be some export restriction prohibiting me from posting it to you in NZ. What about the NZ end? Any import restrictions on brass?
 

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