6.5 WSSM Bolt Lift Problems???

C

C. Ballard

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I am working will a 6.5 WSSM based of the 25 WSSM case. I have obtained the desired velocity with no pressure signs on the case, but the bolt is hard to lift. The necks have been turned and have plenty of clearance. The only thing I could come up with is, the brass is so thick it isn't spinging back. I was hoping someone on this forum has had this problem and found a solution. Any help would be appreciated.

Thanks, Charles
 
The problem is inherent to the case design. It's too fat for its length. The only way to approach the problem is to keep pressure down IMO. In my limited experience factory actions are worse than customs because of flex.

al
 
Might be wrong but it sounds to me like you don't have enough metal around the chamber.
How large is the action tennon?
You know, factory actions for WSMs use larger diameter barrel threads..

I used a BAT RS to prevent this
 
Step up to the next faster powder in burn rate and it'll probably go away.
 
I am using a large custom action and the new reloader 17, I have tried H4350 and h4831sc both of these powders give me harder bolt lift. I know 4831 is slower, but thats what I have read that worked. I have also tried Varget, at 39 grains you have to tap the bolt open. Thanks for any info.

Charles Ballard
 
I have been using a 6.5/25wssm for 4 years.I also have a 243wssm.they both are on rem 700 actions.my wssm's both bolts open fairly easy and shoot good also.you have to run them full tilt or the bolt will open hard.the front of the case exspands faster than the sides at low pressure and drives the case head into the bolt face.this is what causes hard bolt lift at lower pressure.Please post back with what your load is and wth barrell you have.I think you need more powder.
 
Make sure that your chamber and brass are completely free of any lubricant residue. Clean both with alcohol or something else that will reliably degrease, and try again. A friend who used to "dry" his chambers with a reused chamber swab had some problems with the first couple of shots after cleaning. (6 BR) Using alcohol on a clean patch on the chamber solved the problem. This may not be the total answer, but it may be part of the problem. Also, simply wiping lube off of cases does not remove it all.
 
Charles, is your headspace changing on these firings?
How much do you bump?
Is there growth .200 up from the heads?
Are these chambering easy?

Whats your barrel threading?

I ask because hard bolt lift is not 'normal' with any cartridge.
 
To answer the question as to the load. I shot 45 grains of H4350, 48 grains of H4831sc both with real hard bolt lift, so I quit using those powders. The only load I could get a manageable bolt lift was with 44 grains of reloader 17 with 215m primers shooting the Berger VLD 140's. This load cronos at 2950. I have also tried cci br-2 primers and 210m's. I am shooting a Broughton 5c. We are having the same problem with a buddy of mines rifle, he is using another brand.

Thanks for any help, Charles
 
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Mike,

My headspace isn't changing.

In most cases I only bump 1/2 a thousanth I have bump these as much as
.002.

The head grow from new brass about .003 nothing after the first firing.

A resized case still chambers hard even with shoulders bumped .002.

As far as the barrel threading I think it is 1.062 with 18 tpi. but i'm not sure.

Charles
 
C. Ballard said:
To answer the question as to the load. I shot 45 grains of H4350, 48 grains of H4831sc both with real hard bolt lift, so I quit using those powders. The only load I could get a manageable bolt lift was with 44 grains of reloader 17 with 215m primers shooting the Berger VLD 140's. This load cronos at 2950. I have also tried cci br-2 primers and 210m's. I am shooting a Broughton 5c. We are having the same problem with a buddy of mines rifle, he is using another brand.

Thanks for any help, Charles
Click to expand...

A hard bolt lift is a pressure sign. Your pushing those 140's super fast for a wssm don't you think? Drop 2 grains IMO.

Cheers
 
I don't think he's pushing anything.
I run ~47.5gr IMR4350 for 3025fps from a 28" barrel. I've pushed it to 3200 before getting any real changes to the brass. Over 20 reloads so far, with very little body sizing, and about a thou of bump each time. My brass has grown .0015 at the web from new.

My barrel threads are 1.125"X16tpi
Savage WSM/RUM/SAUM barrels are also larger than standard at 1.120x20 t.p.i. and use a larger barrel nut.

The WSSM pretty much matches the 260 in capacity, and slightly betters 260 performance. It's brass is as good as it gets -after turning.
So this isn't a cartridge issue.

It sounds like a combination of the action chosen(too small), and chamber(loose) to die match.
Do you know if your action is commonly used with magnum size cartridges?
 
Hard Bolt lift..

Hey Charles:

Thanks for the voice mail reply the other day. You save my bacon. The reamer I had ordered was out of spec to my needs.

With your barrel removed from the action Take a unfired sized case and see if it will fit the chamber easily with a finger push until it seats fully on the shoulder. Then try removing it with your fingers. If it takes the aid of something to pull it out besides your fingers then your neck shoulder area may need polishing. Or your brass may be to long. If the case stops around the .200 mark (webb) then your chamber needs polishing in that area. Some folks address this with small base dies. I personally think that polishing this area is a much better answer. If you are using a PT&G reamer and Ray is setup properly aligned, as I would expect of him, then the chamber may be slightly undersized due to reamer flex during the reaming process. That is a good problem to have as it is easier to remove metal than put it back. I have encountered more tight chambers than loose chambers with a correct setup. I have several reamers that I expect to have to polish the chamber, especially with Lapua brass, Nosler brass, and Norma brass. You want both your sized brass and your fired brass to come out with little or no resistence. I think with polishing your chamber your problem will go away.


Nat
 
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In most cases I would agree that hard bolt lift is a pressure problem, but not in this case. I get a hard bolt lift with all loads from 2600 all the way to 3050. Most people who are using this case with match winning success are getting 2950-3000 fps.

As to the action/threading size. Thia is a large ring custom single shot action, 2 of my F-class national records were shot with this action as a 300WSM. I was pushing 210 VLD's @ 2875. I understand your thinking on this, this was the fisrt thing I thought of, but we are experiecing this with 2 rifles, the only common link is, the same lot # of brass. Something I have checked since my last post was the case runout on a new and once fired case. It is out of round on the case head on both pieces.

Before somebody post that the chamber is out of round. This was checked and the chamber is perfect.

Nat thanks for the possible problem, but I polish all my chambers. Once the bolt lifts, it extract normal.

As for using the sandpaper to buff a little off the case, that makes since. I will try that. The only question I have is why does it still do this with new brass.

Thanks for all the feed back, Charles
 
C. Ballard said:
In most cases I would agree that hard bolt lift is a pressure problem, but not in this case. I get a hard bolt lift with all loads from 2600 all the way to 3050. Most people who are using this case with match winning success are getting 2950-3000 fps.

As to the action/threading size. Thia is a large ring custom single shot action, 2 of my F-class national records were shot with this action as a 300WSM. I was pushing 210 VLD's @ 2875. I understand your thinking on this, this was the fisrt thing I thought of, but we are experiecing this with 2 rifles, the only common link is, the same lot # of brass. Something I have checked since my last post was the case runout on a new and once fired case. It is out of round on the case head on both pieces.

Before somebody post that the chamber is out of round. This was checked and the chamber is perfect.

Nat thanks for the possible problem, but I polish all my chambers. Once the bolt lifts, it extract normal.

As for using the sandpaper to buff a little off the case, that makes since. I will try that. The only question I have is why does it still do this with new brass.

Thanks for all the feed back, Charles
Click to expand...

Wondering if you have any traces of brass stuck on your boltface? any distinct markings on your brass? I shoot this case and have never had the problems you are talking about. Hope you find it and make it work. Ron Tilley
 
do you aneal your brass? If not you need to with any wssm,I put them in a fry pan and fill with water half way up the case body and toast them good with mapp gas.this will make the case body expand to grip the chamber walls and stop the case head from being driven into the bolt face.also ditch the 215 primers and go to cci250's or 210's.215's give to high a pressure spike and are not needed to lite 45-50gr of powder.they also make accuracy worse,been there done that.250's will give 15fps over 210's just a little hotter.your 4831sc load is hot with a 215. give me a call I can anser many of your questions better on the phone. martin dailey I will pm you my #
 
Lynn and 6.5 fan thank very much you, I will try the trick with the sand paper tomorrow. I will also check my e-mail and call 6.5 fan tomorrow and discuss it more in-depth.

Again thanks for the help, Charles
 
Charles,

Some good suggestions given by several others. Those real short cases have to grip the chamber walls real good or bolt thrust goes way up and stiff bolt lift will occur as a result. The Broughton 5C barrels are fast, real fast. I think you could go even higher on your powder charge as someone else suggested. I can get 125-150 fps more from a 5C barrel than I can a conventional rifled barrel. Of course you have to load the speed that shoots good too.

Joel
 
J. Pendergraft said:
Those real short cases have to grip the chamber walls real good or bolt thrust goes way up and stiff bolt lift will occur as a result.
Joel
Click to expand...

Mr. Joel Pendergraft, would you believe, that most observants will agree.

Con
 
Joel,

Thank you for that info. I have order some new brass to eliminate a bad batch of brass. I was planning on pushing it a little harder when I get the new brass. So what your saying about the bolt thrust is:that the case is not blowing out to the case walls as quick as the shoulder are blowing out to the front of the chamber. Thus running it at higher pressure will reverse this process. The only concern I have is; I have run this case hot to about 3050 fps and started seeing shinny spots on the back of the case from the ejector hole, with an even harder bolt lift, so I backed it back down to 2950. Please keep the ideas coming.

Thanks again, Charles
 
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