Brass shot from factory remington 7RUM too tight in new Mc gowen barrel?

[Max Heat]

My new 32" barrel seems like it has a LOT tighter tolerance than the factory (non-sendero) SPS barrel. I don't really have a problem with that, as I DO go along with the "tight-is-right" line of thinking. But it has caused my faith in factory barrels to take a turn for the worse.

Cartridges (un-resized) fired out of the new Mcgowen barrel can be cycled back through the action without any problem. But whan I try to due that with un-resized brass that was previously fired out the the factory rem barrel, it is a straight-up no-go! Right off the bat, it's obvious that the neck just isn't going to fit [without hammering it in]. But then you'd probably never be able to remove it from the chamber.

Now THIS is the kicker: Upon re-sizing (which is NOT easily accomplished), the brass can now be coaxed into the chamber, but not without "some" difficulty. It is still tight enough that the extractor can't pull it out. It has to be "knocked" out. Presently, I am using fresh cases in the new bbl, but they will be running out soon. And compared to what I have from the old barrel, there aren't very many out of the new one.

Is this a common situation, or do I need to start "dissing" factory Remington barrels?

If I chamber and fire the resized and reloaded [but still un-extractable] cartridges out of the new bbl, is it reasonable to expect that they will be "formed" back down to size, and be able to be extracted there-after?

 

[Deleted member 46119]

Basically all you ask about is 'normal'.

Cases fired from one rifle to another may not chamber without full length sizing to match the new chamber.

Necks can be part of the challenge as well.

No need to diss factory barrels, they are as they should be. Your new barrel should be tight.

I have the same for my target 300 RUM vs the hunting 300 RUMs.

You may need to adjust your die.

or

You may need a 'shorter' case holder so you can size a little farther down.

 

[Max Heat]

The sizer die IS adjusted ALL the way tight (tight-is-right). Shell holder plate thickness does NOT matter.

Other question I asked was, will shooting the still-tite-after-sized cases out of the new barrel fire-form them "down" to a not-so-tite fit the next time through, after they are sized and loaded again?

Or can I expect that those cases to ALWAYs be tight, in the new barrel?

 

[Jud96]

Factory Remington barrels are very grear and have nice,, tight chambers which is a good thing.

 

[MontanaRifleman]

The sizer die IS adjusted ALL the way tight (tight-is-right). Shell holder plate thickness does NOT matter.

Uhhh... yes it does. If you lap the top of the shell holder off, you can screw the die down farther and bump your shoulder farther. That said, you can screw down your die another 1/8th to 1/4 turn after your die is bottoming out on the shell holder. If you still aren't getting them to chamber easy, then I would recommend shaving either the bottom of your die off or the top of your shell holder. I prefer doing the bottom of the die.

This isn't that umcommon with tight custom reamers. I just had to have 10 thou shaved off the bottom of 3 of my dies (for 2 rifles) shaved off and one of them I am still camming over 1/8th of turn.

Other question I asked was, will shooting the still-tite-after-sized cases out of the new barrel fire-form them "down" to a not-so-tite fit the next time through, after they are sized and loaded again?

Or can I expect that those cases to ALWAYs be tight, in the new barrel?

As previously mentioned, I would FL size them down until they fit the new chamber. Then I would anneal them and size them again. Do not mix old brass fired from another rifle with new brass. Bad juju. It will shoot, but you might not like the results.

The RUMs are wild critters and the available brass sucks. I am getting some Bertram made 338 EDGE brass for mine.

Good luck

 

[BountyHunter]

Couple things.

1. Factory chambers tend to be on the large end of SAAMI specs while custom chambers are often on the small side.

2. Your problem could be shoulder and could be the the lower body and your factory die may not size the body enough regardless of where the shoulder is. Measure the body of the sized brass. uou might try a small base die to fix it.

3. Tight is not always right. You must adjust the die to just bump the shoulder in spite of every thing else .

 

[Gunpoor]

I had a Shilen barrel in 264Win and later had another custom barrel in 264Win for my TC Encore and the brass fired in the Shilen wouldn't size down enough to chamber in the Encore. Ended up buying new brass and never had any issues with it. That is just the way it is sometimes. I think the belted magnums are more prone to this type of issue than non-belted cases because the belted cartridges headspace on the belt rather than on the datum line of the shoulder, with the rest of the case dimensions are all over the spectrum with the belted mags as long as the belt is SAAMI correct. I don't like the belted cases because of this issue,though I won't argue that there are some accurate rifles chambered for belted case cartridges but they are more prone to chamber size issues.

 

[varmintH8R]

2. Your problem could be shoulder and could be the the lower body and your factory die may not size the body enough regardless of where the shoulder is. Measure the body of the sized brass. uou might try a small base die to fix it.

+1. I had an LRH member send me a once fired 338LM case to drill and tap for use on my Hornady OAL gauge. My OCD wouldn't let me sacrifice a shiny new piece of Lapua brass....

The case had expanded in his chamber (just forward of the case head) and no amount of sizing with a Redding body die was going to make it chamber smoothly. I could measure it with a micrometer and clearly tell the difference. I jammed it to fire it, but that didn't allow it to be sized to fit in the future (if you think about it, you really wouldn't expect it to). Had my neighbor turn the bottom of the case down a few thou on a lathe, and it now slides right in. I certainly wouldn't recommend that solution for cases you intend to fire

Never an issue with new brass that has only been fired in my rifle. I'm on 6 loads and regular sizing leads to an easy fit.

As MontanaRifleman said, mixing brass between rifles is bad juju.

Brandon

 

[BountyHunter]

I had a Shilen barrel in 264Win and later had another custom barrel in 264Win for my TC Encore and the brass fired in the Shilen wouldn't size down enough to chamber in the Encore. Ended up buying new brass and never had any issues with it. That is just the way it is sometimes. I think the belted magnums are more prone to this type of issue than non-belted cases because the belted cartridges headspace on the belt rather than on the datum line of the shoulder, with the rest of the case dimensions are all over the spectrum with the belted mags as long as the belt is SAAMI correct. I don't like the belted cases because of this issue,though I won't argue that there are some accurate rifles chambered for belted case cartridges but they are more prone to chamber size issues.

IF you have a true riflesmith instead of just a gunsmith, it is easy for them to chamber off the shoulder instead of the belt and end of issues.

 

[Gunpoor]

Messed up

 

[Gunpoor]

"IF you have a true riflesmith instead of just a gunsmith, it is easy for them to chamber off the shoulder instead of the belt and end of issues."

Bounty Hunter, you are probably 100% correct about that. The gunsmith I had build my FN Mauser with the Shilen barrel in 264Win left the chamber area ahead of the belt so long I had to neck size only in order to save my brass.

 

[lazylabs]

Bounty..... what you said makes no sense. riflesmith vs gunsmith? There are two types of gunsmiths, talented or not.

 

[varmintH8R]

Bounty..... what you said makes no sense. riflesmith vs gunsmith? There are two types of gunsmiths, talented or not.

Is your assertion that a talented gunsmith cannot be specialized? If so, I disagree. There are a bunch of smiths that haunt this site that I would gladly pay a premium to for building a long range rifle. For a competition-specific 1911, I wouldn't even consider them. Same for a custom 3-gun AR.

There are definitely those that specialize in nothing, but to simply state that smiths are either talented in everything or not talented at all is a little too black and white for me.

Brandon

 

[lazylabs]

I was just refering to bounty saying "just a gunsmith" not a riflesmith. If you want to specialize fine.... call yourself a gunsmith, riflesmith, pistolsmith whatever. If you accept the work either you have the skills to properly do the work or not. To say that someone is producing quality work based on what they call themselves? Let's not forget anyone can start a company and call themselves any of the "smiths" they chose to.