Bolt closes hard, with reloads

[Touch not Squeeze]

Hi Forum, I have a 7mm Rem Mag in a M77 chasis. I do have an issue with the bolt closing. Now, I have only seen this with the reloads, and what happens is the bolt close a little tougher than factory loads. I did partially resize the cases, and I was thinking that was the issue. With a fire formed case, will it be more apt for it to close harder, than a full length resizing?

 

[Accubond Believer]

T n S -

Two things to check - case length - brass may need to be trimmed
total cartridge length - may need to seat bullets deeper

Take one of you handloads and chamber it - remove and examine cartridge to see if there are rifling marks on the bullet - if rifling marks are there you need to seat the bullets deeper.

Steve D. the HP

 

[Glock Man]

I would recommend that you full length resize your brass. You might have a tight chamber that will only accept brass that way. I personally have found Rugers to be finicky.

 

[SOTN]

Hi Forum, I have a 7mm Rem Mag in a M77 chasis. I do have an issue with the bolt closing. Now, I have only seen this with the reloads, and what happens is the bolt close a little tougher than factory loads. I did partially resize the cases, and I was thinking that was the issue. With a fire formed case, will it be more apt for it to close harder, than a full length resizing?

I think you're right. Far and away, the most likely cause of the problem is your “partial FL sizing”.

When you partial size, the forward part of the body is sized down some, and it has to go someplace so the shoulder gets pushed forward, making for a too tight fit.

With many die and chamber combinations, Partial FL sizing doesn’t work well, depending on how it is defined of course. With a FL die, it’s best to FL resize, but just don’t adjust your die so the shoulder is pushed back farther than is needed.

In any case, if fire formed cases fit OK, the neck isn’t waaay too long, and the bullet isn’t touching the lands, you just need some more sizing. Try the sized cases before you seat the bullets. It helps to remove the firing pin assembly from the bolt for a better feel when chambering the cases.
Smitty of the North

 

[Touch not Squeeze]

T n S -

Two things to check - case length - brass may need to be trimmed
total cartridge length - may need to seat bullets deeper

Take one of you handloads and chamber it - remove and examine cartridge to see if there are rifling marks on the bullet - if rifling marks are there you need to seat the bullets deeper.

Steve D. the HP

The first thing I checked was cl and oal, and they were perfect. No rifling marks on the bullet.

 

[ranger140892]

Most likely it's an egg shapped or "out of round" chamber. Most factory rifles are that way. Unless you get the case back in the chamber oriented the same way it was when it was last fired, it will be hard to chamber.
Check case length and bullet seat depth first. If it's ok, try a small base die.

 

[Touch not Squeeze]

Hi Forum, I have a 7mm Rem Mag in a M77 chasis. I do have an issue with the bolt closing. Now, I have only seen this with the reloads, and what happens is the bolt close a little tougher than factory loads. I did partially resize the cases, and I was thinking that was the issue. With a fire formed case, will it be more apt for it to close harder, than a full length resizing?

I think you're right. Far and away, the most likely cause of the problem is your “partial FL sizing”.

When you partial size, the forward part of the body is sized down some, and it has to go someplace so the shoulder gets pushed forward, making for a too tight fit.

With many die and chamber combinations, Partial FL sizing doesn’t work well, depending on how it is defined of course. With a FL die, it’s best to FL resize, but just don’t adjust your die so the shoulder is pushed back farther than is needed.

In any case, if fire formed cases fit OK, the neck isn’t waaay too long, and the bullet isn’t touching the lands, you just need some more sizing. Try the sized cases before you seat the bullets. It helps to remove the firing pin assembly from the bolt for a better feel when chambering the cases.
Smitty of the North

OK, in regards to you and Nosler3's point. These cases were fired formed in this rifle. I am not sure how it is possible that I could have made the diameter of the case wider when resizing, thus producing the firm bolt closure. Do you guys see what I am saying? Additionally, is the extractor typically moving around of the rim of the case, or is the case turning. I guess I will need to look at the rim to make sure it isn't carved up.

 

[Touch not Squeeze]

Most likely it's an egg shapped or "out of round" chamber. Most factory rifles are that way. Unless you get the case back in the chamber oriented the same way it was when it was last fired, it will be hard to chamber.
Check case length and bullet seat depth first. If it's ok, try a small base die.

That's very interesting! I will have to get taper gauge and see if I can see it with that. Thanks for the thought.

 

[Ol` Joe]

OK, in regards to you and Nosler3's point. These cases were fired formed in this rifle. I am not sure how it is possible that I could have made the diameter of the case wider when resizing, thus producing the firm bolt closure

The case body isn`t wider when resized it acually "grows" longer in the measurment of base to shoulder datum. Think of squeezing a balloon. You compress the "body" of the balloon and it "squirts" foreward. The same happens with cartridge brass only it doesn`t return to its original state. This causes the case to bottom out before it is all the way in the chamber. ou are likely setting the shoulder back with the rifles bolt rather then with the sizeing die.

The expander ball in some instances will drag enough on the inside of the case to "pull" the shoulder foreward also. The die needs to just bump the shoulder back enough to off set the brass movement from the resizing operation. Lubeing the inside of the neck with a dab every couple cases will help prevent expander drag.

I would color a fired EMPTY case shoulder with magic marker or soot from a candle and with the die backed a half to a full turn off the ram at top dead center size the case. If the ink or soot isn`t wiped off 1/2 or so of the shoulder screw the die 1/8 deeper and resize until it does. Try chambering the case and see if it enters your rifle smoothly. If not add a bit more to the sizeing. Be sure to lube the case mouth when doing this, a Q-Tip with a touch of lube will do a dozen cases easily-don`t over do it.
Let use know what you end up finding

 

[Touch not Squeeze]

OK, in regards to you and Nosler3's point. These cases were fired formed in this rifle. I am not sure how it is possible that I could have made the diameter of the case wider when resizing, thus producing the firm bolt closure

The case body isn`t wider when resized it acually "grows" longer in the measurment of base to shoulder datum. Think of squeezing a balloon. You compress the "body" of the balloon and it "squirts" foreward. The same happens with cartridge brass only it doesn`t return to its original state. This causes the case to bottom out before it is all the way in the chamber. ou are likely setting the shoulder back with the rifles bolt rather then with the sizeing die.

The expander ball in some instances will drag enough on the inside of the case to "pull" the shoulder foreward also. The die needs to just bump the shoulder back enough to off set the brass movement from the resizing operation. Lubeing the inside of the neck with a dab every couple cases will help prevent expander drag.

I would color a fired EMPTY case shoulder with magic marker or soot from a candle and with the die backed a half to a full turn off the ram at top dead center size the case. If the ink or soot isn`t wiped off 1/2 or so of the shoulder screw the die 1/8 deeper and resize until it does. Try chambering the case and see if it enters your rifle smoothly. If not add a bit more to the sizeing. Be sure to lube the case mouth when doing this, a Q-Tip with a touch of lube will do a dozen cases easily-don`t over do it.
Let use know what you end up finding

ok, I will report back. What is weird, is that it does it inconsistantly, but maybe that makes sense. I didn't notice it, but my dad did as it is his gun. The Wisconsin whitetail season starts in three days, so we might have to mak do for now, unless you think there will be problems.

 

[clearwater]

I had somewhat similar problem and it ended up being the die.
I bought a $10 set of lee RGB dies to try and that fixed the problem.

 

[SOTN]

Ol' Joe is "right on the money".

Simply put, you just haven't sized the case enough.

The die sizes the neck, and the body. While the body is being sized, it can lengthen the shoulder, then the shoulder has to be bumped, or sized back again. This all depends on how you adjust your FL die.

As I said, this is the most likely cause of the problem, and should be addressed before looking for something wrong with your rifle or dies.

Good Loadin & Good Shootin.
Smitty of the North

 

[Touch not Squeeze]

Thanks everyone!

 

[rick smith]

Touch, remove the expander ball and assembly from your FL die and size a fired case, remove lube and try it in the rifle. If it fits, try another fired case with the expander ball assembly in place and try that in your rifle. Use a different case each time you try. Also while you have the expander ball out of the die, polish it to a mirror finish. I use a dry lube on the case necks for sizing. You need to know if it is the sizing or the ball causing the problem.Rick.