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Heavy bolt lift

Pizzadude

Apologies if this has been discussed ad nauseum.
New HOWA Barreled action in 6.5 CM.
MDT XRS Chassis
129 gr Winchester Target and Practice, NEW FACTORY ammunition 125gr open tip.
I am experiencing a heavy bolt lift with what I consider an excessive amount of brass on the bolt face, after ejecting a FIRED round.
Live ammunition chambers easily, but once fired-I experience a heavy bolt lift from the minute I lift the bolt.
I have measured the base of the case just above the ejector groove on the unfired ammo, it measures-.466".
I have measured the base of the case just above the extractor groove on FIRED ammo, it measures-.470".
I have also shot 3 reloaded rounds-the cases were x2 Peterson brass, completely FLS on my Redding dies and shoulders were bumped 1.5525".
I'm going to the range tomorrow with some NEW Hornady Hunter ammunition. 143gr ELDX. Shoulders measure 1.550". I want to see what the new Hornady ammo does with the shoulders what they are.
 
If you want your brass to last longer your max. Measurements should only be 1/2 thousands .0005. Your measurements of your new brass of.466 once fired should be no more than .4665.If you are going to reload,l would use lapua brass. That ammo you shoot in your rifle chamber is way over pressure or your chamber is over sized.
 
doctorh said:
If you want your brass to last longer your max. Measurements should only be 1/2 thousands .0005. Your measurements of your new brass of.466 once fired should be no more than .4665.If you are going to reload,l would use lapua brass. That ammo you shoot in your rifle chamber is way over pressure or your chamber is over sized.
Click to expand...
I gave that consideration. I do not load hot rounds for any of my rifles. All are by the listed charges ,all under max. There are no pressure signs-no flattened primers, no ejector strike marks.
 
Pizzadude said:
Apologies if this has been discussed ad nauseum.
New HOWA Barreled action in 6.5 CM.
MDT XRS Chassis
129 gr Winchester Target and Practice, NEW FACTORY ammunition 125gr open tip.
I am experiencing a heavy bolt lift with what I consider an excessive amount of brass on the bolt face, after ejecting a FIRED round.
Live ammunition chambers easily, but once fired-I experience a heavy bolt lift from the minute I lift the bolt.
I have measured the base of the case just above the ejector groove on the unfired ammo, it measures-.466".
I have measured the base of the case just above the extractor groove on FIRED ammo, it measures-.470".
I have also shot 3 reloaded rounds-the cases were x2 Peterson brass, completely FLS on my Redding dies and shoulders were bumped 1.5525".
I'm going to the range tomorrow with some NEW Hornady Hunter ammunition. 143gr ELDX. Shoulders measure 1.550". I want to see what the new Hornady ammo does with the shoulders what they are.
Click to expand...
are you saying the web of the case grew .004” after firing?
 
What happened with your reloads? Some folks have reported about factory loads being too hot. How many rounds have you shot thru the gun?
 
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.
 
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ShtrRdy said:
If you dry fire the rifle without a cartridge in the chamber how does the bolt lift feel?
Click to expand...

J_idaho said:
are you saying the web of the case grew .004” after firing?
Click to expand...
I've never heard of it referred to as the "web". The area I am referencing is immediately above the extractor groove. And yes it did expand by .003-.004". Live round on the left measures-.467". Fired round on the right measures-..471"
 
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Pizzadude said:
See pics below Bill
Click to expand...
I saw them and I don’t see any pressure signs, just like you said already. I’m just watching the thread now, hoping somebody else figures it out. I have had some issues with heavy bolt lift that got solved by using a slightly smaller die, but the expansion you are seeing from 0.366 to 0.370 after just one shot seems like a lot and most likely an issue that I’m not familiar with. I don’t use any Hornady or Winchester brass or factory ammo now. I have shot some 6.5 Creedmoor Hornady factory ammo in the past but in an open bolt rifle so I wouldn’t have noticed a bolt lift issue.
 
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I’ve only seen this problem on rough chambers that needed polished a bit and then roughed back to a 600 grit finish. Or running to hot with first firing with chamber size close to saami max. From a reloading stand point they should work after first firing as long as you don’t over size the cases which creates over pressure with a faster powder. It could be a combo of both. You never posted shoulder measurements after firing.
 
Someone already mentioned the possibility of an over large chamber, I wonder if this might be the issue?
If a chamber cast can be made and measured perhaps that will shed some light.
Possibly a defect from the factory...?? Reamer run in too deep??
Just guessing here...
 
Not questioning, just asking the question: It doesn't appear that those 2 measurements are taken in the same place.... Are they? An easier way for me to do it is to lay the calipers flat on the bench and stand the brass (primer removed) up between the jaws. Better consistency that way for me. There are gauges/jigs to assist with this as well.
 
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