tight bolt on closing

stalkinginengland

Well-Known Member
Have had great success with loading the 243 worked the load up and ver pleased with results. However the bolt has seemed tight possibly too tight. Cases have been FL sized and trimmed bullet head set back by a couple of thou. What's gone wrong? Groups are great. Any ideas



Regards

Mark
 
Does the seating die cover the whole round?

I've recently had a situation where the die has created a small bulge right at the bottom of the round to the extent that I couldn't chamber the round at all - now changed dies that seat completely on full length and fine. Just check you don't have a slight widening of the round at the base as this is one cause of a tight bolt.
 
hi bud is the bolt tight before or after firing if before firing i think round is getting pushed up the lands to far forward if after firing over expanson of case to much powder /note remove all lube from your cases as lube left on results in lots of back presure case being hAMERED BACK ON THE BOLT FACE RESULTING IN TIGHT BOLT LIFT WET ROUNDS FROM THE RAIN CAN DO THE SAME THING AS THE ROUND CANT GRIP THE WALLS OF THE CHAMBER AND TRIYES TO GO BACK RATHER THAN SIDE WAYS im no expert but hope it helps
 
Ive recently had exactly the same problem! Do as muir said and back the die off a touch. Also, make sure the sizing pin is clean and you're not dragging the case out on the upstroke lengthening the case slightly. Double check your breach is clean too, a slight build up of detritus will give similar problems.
 
What press and dies are you using ? I use RCBS Rockchucker and RCBS full length dies. I had this problem several years ago and the reason was that I had set the die so that the press didn't cam-over, consequently the shoulder was not sufficiently pushed back. The cases I was using had been fired in another rifle. If you are using cases fire formed in the same rifle then this is unlikely to be the cause of the problem and you will need to look at other possibilities as outlined by other members.
 
Thanks so far. I am using a RCBS full length die and the cases have been trimmed to length and chamfered inside and out. I am using a lee press.

So that I understand, why would backing the die out help? I am asking this as I want to know the tecnical reason for it. I imagin that this means the case would not go into the die as far , what advantage would this make, my idea would be that the shoulder and neck would not be sized in the same way or in the case of the shoulder ,not be pushed back as far. How does this help.?

Mark
 
First size a case and ten try it in the chamber. if it's still tight then you sizing set up is not quite right.

If is goes in fine that you causing the problem elsewhere. I have seen many a .243 case with slightly bulged shoulder/wall juncture. Often is the seating die screwed down too far and is crushing the case neck into the body causing the bulging.

If that is not the case here then seat the bullet deeper. To test take a newly size unprimed case and wind the seating stem of the die in one FULL turn then seat a bullet into the unprimed case then try in the rifle.

Doing this will highlight where you problem is and why it's happening.

Have fun and let us know how it goes.

Press make and die make will make little difference it's the set up of them that is the problem most likely.
 
I don't reload, no knowledge of the subject other than reading SD. But people go on about fire forming. Are you using second hand cases fire formed in someone else's chamber. Just a thought?
 
I will go with Brithunter here - if your seating die is not set up properly, when you seat a bullet the press could easily push the neck back to give a doughnut effect near the base of the neck and so cause difficult bolt movement.

You say the bullet is set back a couple of thou ? If you really mean that you are seating the bullet a couple of thou off the lands and possibly measuring without a comparator on the ogive and bearing in mind bullet length can vary up to 12 thou sometimes - then that could be your problem.

For the record, unless you have a custom benchrest rifle with a custom made chamber, I would suggest you are very unwise to seat your bullets so close.
 
have you given the rifle and bolt receiver a damn good clean i had this problem with my 22250 the bolt was hard to close turned out was a build up of debris in the receiver cleaned it out alls good now
 
Are you sure that the case was trimmed to the correct length, if you have the culprit case have a good look at it and measure it? it may also be the shoulder is not being bumped back enough. I reload quite a few .223 and only a few .243 so a liitle inexperinced with this problem in .243.

I very occasionally have had the same problem in .223 neck sized only and will resort to running the case through a FL die.

D
 
if they are your cases fireformed in the same rifle they would chamber perfectly before you FL sized them!
bumping the shoulder back further will not make chambering so much easier.
I use fireformed case with nothing more than a outer neck size and the chamber perfectly, why wouldnt they? they have been matched to the chamber!

only reason a case would not chamber after a FL resize is if either the die FL or seating is deforming the case outside the chamber specs

if you chamber one, crank the bolt you will see a shiney ring where the pressure is.
My money is on the base of the shoulder or the outer rim of the neck
 
We just can't diagnose the problem from here. The poster needs to take matters into his own hands and figure it out.~Muir
 
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We just can't diagnose the problem from here. The poster needs to take matters into his own hands and figure it out.~Muit
agreed, but if I were a gambling man then I'd say it's a seating die wound in to the point of crimp that's making the shoulder bulge. :oops:
 
agreed, but if I were a gambling man then I'd say it's a seating die wound in to the point of crimp that's making the shoulder bulge. :oops:

That too. I am just a bit flummoxed at folks who are still vague on die adjustment. I guess I've been at it to long. It's 2nd nature to me...~Muir
 
Hi - I've been reloading various calibres for some time so I hope this helps.
If the bolt is hard to close when you chamber a round then the round is too big in some way. It could be the case size or the bullet isn't seated deeply enough. What you may be doing here is seating the bullet a bit more with your bolt which is a bit harder to do than than with your reloading press.
If the bolt is only hard to open once you've fired it's a sign of too much pressure. You can check this by examining the primer on the spent case. The primer will be protruding more/possibly mishapen if there's too much pressure. There may also be marks/shiny abrasion on the case head from the bolt. There are many things that can cause there being too much pressure but too much pressure blows up rifles and hard extraction is a warning sign.
What you can try if you've still got the problem is; take an UNPRIMED case you've trimmed, seat a bullet in the way you have before and try to chamber it. If its too big, when you unload it after you've chambered it you'll find marks from the lands/rifling of your barrel on the bullet.
I'm writing this in the spirit of trying to help and you've any questions please PM me.
I'd ask any experts out there who feel the need to add replies which try to make me look foolish but don't help answer the thread to PM me instead.
 
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Not trying to make you or anyone else foolish "awmc" but trying to read primers for pressure signs is difficult as different makes vary in hardness of the cup material and also the tightness and quality of he chambering and breeching up of the barrel.

For instance Petersens Rifle Shooter magazine did a test with a pressure gun on the 30-30 Winchester case and they got well over proofing pressures before the primers showed any signs of excessive pressure. They recorded a chamber pressure of excess 80,000 psi before the primer pocket expanded and this is on the supposedly weak 30-30 Winchester case. I cannot check the actual figure as the article is in an a magazine taken into custody in March 2011.

Also the suggestion to try chambering a sized un-primed case was made back on the first page.

Just a suggestion but if one want to read marks on a case being chambered then covering the case with ink from a permanent marker works fairly well when allowed to dry before attempting to chamber it. The same on a bullets ogive will show any and how much engagement with the leade.

I have used both methods in the past when playing with projects.
 
post a pick of a case prepped and 1 loaded.
RCBS and redding seating dies have a roll crimp built in which only comes into play when the die is wound down to the shell holder.
if your bullet doesn't have a cannelure then it will bulge the shoulder and cause a hard close but may not be patently obvious at first. it only needs to be a few thou to be trouble.
 
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