whats does it mean when the bolt is hard to close?

[lordt313]

I was shooting yesterday, on my 10th cycle with this brass, and I noticed that I was really having to torque down the bolt handle to get the rifle to chamber, I OAL resize every time and by all measurements the brass is is actually trimmed to 2.006, what would case this difficulty in chambering? Could it be my chamber is dirty and needs to be cleaned really well? Could it be the walls of my brass are bowing? (although I measured this too and it was good). I dont crimp my rounds and am doign some laod development so here are the COAL for the laods 2.806, 2.815, 2.840, 2.862, 2.880. Would it maybe be that the resistence was the COAL was too long and I was actually pushing the bullet seat depth down?

The brass in question is FGGM and I have loaded it 10 times since its intial firing.

Thanks,
Taylor

 

[dmg308]

Re: whats does it mean when the bolt is hard to close?

One thought resize one case and see if it chambers properly.If its tight you may need to adjust your dies to bump your shoulder back a bit.

 

[lordt313]

Re: whats does it mean when the bolt is hard to close?

DMG, I meant to mention that in my original post, you think it could be that? I did take aprt the die to clean it before I loaded the last batch, thats probably it, thank you for showing me what I should ahve figured!!

-Taylor

 

[Raven 6]

Re: whats does it mean when the bolt is hard to close?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: dmg308</div><div class="ubbcode-body">One thought resize one case and see if it chambers properly.If its tight you may need to adjust your dies to bump your shoulder back a bit. </div></div>
That was what I was thinking. A RCBS Precision Mic really comes in handy for measuring your case shoulder.

 

[EddieNFL]

Re: whats does it mean when the bolt is hard to close?

If headspace, case and COAL and chamber are within spec, check neck thickness. Had an XP100 in 7MM BR. Brass never got longer, but I had to turn the necks after five loadings.

 

[Hasgun Willtravel]

Re: whats does it mean when the bolt is hard to close?

Bump the shoulder, check the length of your brass, may nee to be trimmed. That may not have as much impact on bolt resitance as shoulder though..

 

[Graham]

Re: whats does it mean when the bolt is hard to close?

If you are full-length sizing your brass, then its most likely a shoulder problem: You may not be getting enough of the case into the sizing die, resulting in squeezing the brass and growing the case, but not getting enough set-back from the die.

 

[Boomholzer]

Re: whats does it mean when the bolt is hard to close?

10 reloads through FGMM, holy crap.
I don't think I ever made it past 4 reloadings.

 

[308isgreat]

Re: whats does it mean when the bolt is hard to close?

If you're full length sizing and correct trim length is not fixing the problem then the necks need to be turned. What happens is every time the brass is fired, the brass actually flows forward on the case. After many firings the brass flow forward will cause the neck to grow in thickness/diameter. Neck turning a few thousanths will get your brass chambering like new.

 

[SmokeRolls]

Re: whats does it mean when the bolt is hard to close?

It's a virgin....Haha...SmokeRolls

 

[Wil]

Re: whats does it mean when the bolt is hard to close?

before you go doing all this...

Check your case web measurements...

You don't mention what kind of rifle this is...

You could be a few thousandths off in the case web and that is where the resistance is coming from...

a small base body die may be needed to fix this...

What type of rifle is this? What are your chamber specs?

 

[FIREMEDIC27]

Re: whats does it mean when the bolt is hard to close?

I think Wil is on the right track. Paint or color you case completely with a black marker then chamber the round. The tight spot should rub off the ink.

I'm having the same problem with new brass in a Win M70 in 7mmRM and the chamber is tight just over the belt. Didn't find it until I painted the case. Food for thought....

 

[MitchAlsup]

Re: whats does it mean when the bolt is hard to close?

It is obvious that something is too big when the bolt won't close. There are several options:

a) primer not seated
b) bullet out too far
c) neck too long
d) web overexpanded
e) sholder too long

Of these, more than 90% of the time its the sholder. Necks rarely cause an issue, primers are obvious when they cause an issue, bullets will show a mark if the lands push them back into the case, and the web will sho scuff marks if extracted without firing.

So, next time this happens:: extract the cartrige, use a magic marker on the sholder, ogive-to-shank transition, web, and primer. Then reload this round, close the bolt, re-extract theis round and examine the case. It will tell you what part is not correct.