beginning of case head separation?

[bob4]

Working up a load of Barnes TSX 180G BT in 300 WM 64gn -66.5 gn of rl-22. 2 rounds gave me a hard bolt lift. Real hard. This is very conservative for this load but the Hornady brass has been fired 7 or 8 times at this point. I brought the 2 pieces of brass home and measured everything I could think of and it all seemed correct. No other signs of pressure so I continued shooting that work up with no other problems at all. That's 2 out of 24 rounds gave me a hard lift.
The only thing I noticed is a ring of scrape marks around the base. None of the other brass shows this. Couldn't feel anything with a paper clip so I split one open and nothing. Pics to follow.
Is this the beginning of case head separation?
One last thing the brass still wont chamber well at all after resizing and pushing the shoulders back.

 

[Shane Lindsey]

I had an old tang safety Ruger that looked like that after a few firings with low end loads. I think the chamber was a little sloppy/loose. Re-barreled and it is now mo-betta.

Is this a factory chamber/barrel?

 

[scottishkat]

Working up a load of Barnes TSX 180G BT in 300 WM 64gn -66.5 gn of rl-22. 2 rounds gave me a hard bolt lift. Real hard. This is very conservative for this load but the Hornady brass has been fired 7 or 8 times at this point. I brought the 2 pieces of brass home and measured everything I could think of and it all seemed correct. No other signs of pressure so I continued shooting that work up with no other problems at all. That's 2 out of 24 rounds gave me a hard lift.
The only thing I noticed is a ring of scrape marks around the base. None of the other brass shows this. Couldn't feel anything with a paper clip so I split one open and nothing. Pics to follow.
Is this the beginning of case head separation?
One last thing the brass still wont chamber well at all after resizing and pushing the shoulders back.

Barnes says 67 to 73gr RL22 in the 300 win mag you really need to be careful firing light loads in magnum cartridges. Sometimes you can get overpressure on the light side as well as over max.

What was the temperature outside when you were shooting? I have not noticed it but some have said RL 22 can be temperature sensitive.

The marks on the outside of the case look like sizing marks to me my redding dies will make the same marks after sizing.

I would increase the charge to within the min max above and start there. H1000 is an excellent choice with heavier bullets in the 300 win mag.

Good luck and shoot straight

Bob

 

[br45zy]

It looks like your full length die is not sizing all the way down to the belt. This can be an issue with belted cartridges.

You can get a collet die that will properly size the brass just above the belt. It does add an additional step in your brass prep but it should cure the difficult to chamber and relieve some of the occasional hard bolt lift your are experiencing.

 

[TJAY]

That sectioned case shows no sign of case head separation.

 

[Deleted member 46119]

Barnes says 67 to 73gr RL22 in the 300 win mag you really need to be careful firing light loads in magnum cartridges. Sometimes you can get overpressure on the light side as well as over max.

What was the temperature outside when you were shooting? I have not noticed it but some have said RL 22 can be temperature sensitive.

The marks on the outside of the case look like sizing marks to me my redding dies will make the same marks after sizing.

I would increase the charge to within the min max above and start there. H1000 is an excellent choice with heavier bullets in the 300 win mag.

Good luck and shoot straight

Bob

Absolutely.

You are sub 90% fill with a sensitive powder in a magnum case. If using a magnum primer as well you may be (probably) creating a secondary pressure wave.

There are a limited number of powders that behave well at fill rates below %90. RL-22 is not known to be one of them.

2 things I see from your description and pictures. JMO but and educated one.

1) your split case picture looks great. From that picture, case head separation is not the problem.

2) the picture provided is very nice quality. Unless there is some form of graphic aberration, I see a bulge at the base of your brass caused by the over pressure secondary wave.

If it were me (IIWM) and not saying you should (anti lawyer Californian)

Use at least the minimum reloading manual charge of 67grains of RL-22 for a 300WM loaded with a 180 TSX. If the problem persists, change powder, primer or both. This is of course standard reloading manual practice.

Do not try to resize the bulge out of the case, it will cause case head separation (physics is physics). Instead, if you want to salvage the brass that is bulged, get: Belted Magnum Collet Resizing Die from Innovative Technologies - Reloading Equipment It's a great tool to have especially of you shoot multiple rifles with belted magnums of the same chambering. Example, I have multiple 300Wby. Each rifle has it's one lot of brass but if I need to move brass from one rifle to the other, I use the collet die as part of the brass preparation.

 

[g0rd0]

I think that the powder you are using is not a good choice. You may want to switch to a powder that burns slower, use a mag primer and not full length size.
I shoot 7rm a lot and when I tried rl22 I had the same issues, went back to imr7828 with cci mag primer by by problems. And I only fl size if I have to. As a side note there are collet dies available that reform the belt if you feel that it is needed.

Every 5th shot I anneal then size I have 118 pcs of FC brass with 12 fireing in them, only fl sized once the rest is neck sized, annealed twice and still showing no signs of wear.

 

[bob4]

I do understand about light loads but I'm a bit shocked at the load data I see some posting only because this is what I'm seeing on their web site. I do not have their book. Now this is for the solid copper bullet.
This pic is from their site tonight. And is what I was going by:

I am using the 180gn TSX BT... Man I hope I'm not missing something here. And I'm certainly glad I didn';t hurt myself or my rifle.
I appreciate everyone's input.

 

[bob4]

I did forget to mention, I am using Mag primers.

 

[scottishkat]

I am surprised to see that big a difference in their new data. The info I gave was from the number 4 hard copy that I have. The odd thing I notice is the significant drop for the 180 TSX which is the same bullet the MRX in my number 4 has a different BC than the ttsx on line. But there is an increase on line for the 165/168 from 75 to 76.1

Look at the huge difference between the 175 and the 180 with RL22 on line.

I'm puzzled now. Which load was giving the stiff bolt lift the 64 or the 66gr?

I still think you may be dealing with lower pressure what is the weight of the brass you are firing? There can be significant differences in brass weight and I am wondering if Barnes used heavier brass in the new load data. The European brass in 300 win mag can weigh 30 or more grains than the win and nosler brass.
For instance my nosler cases weigh 215gr and the PPU weigh 240gr.

I note Norma publishes 2 different sets of load data for 300 win mag now 1 for cases that weigh up to 270 gr and the other light for 215gr there is about 5 gr in the difference. The hornady brass I have weighs 235 gr.

This reduces the capacity of the case thereby creating higher pressures.

I am thinking this may be the difference in the data.

Maybe a call to barnes is in order

Bob

 

[bob4]

I'm puzzled now. Which load was giving the stiff bolt lift the 64 or the 66gr?

Was definatly the 64gn loads.

I still think you may be dealing with lower pressure what is the weight of the brass you are firing?

I weigh some later but it is Hornady.

Maybe a call to barnes is in order

Agreed.
Is the 4th edition their latest ? What do they list for this bullet in your maual using Rl-22?

Bob

Never gave case capacity much thought. Learned something here.

 

[just country]

morning,
168 VLD or 180 TTSX
215
Winchester Brass
4831sc 78.5grs-78.0. work up to both loads.
bug holes

looks like resizing and powder choice. opinionated??lightbulb:gun)

 

[bob4]

Got my hands on a 4th edition manual (didn't buy it). And just like you mentioned. 67-73 gns. I sent an Email out to see what they have to say. That's relay quite a difference although I don't know when the 4th edition was published. I did see a copy-write date of 2008. I would think 6-8 yr old data is getting old. Wouldn't think much of it if I didn't get that hard bolt lift @ 64 gns.

 

[nvreloader]

One of the biggest problems with the 300 mag, is with the Makes/Brands of brass,
QL shows there is 5-6 different INTERNAL CASE CAPACITY'S for the 300 Mag case,
from 87 to 93 grs INTERNAL CAPACITY'S.

Do not mix different brands of brass, or pressure can/will sky rocket in a heart beat,
with normal loads etc.

The best way is to separate all the brass as to brand name and head stamp marking,
ie, R-P with a big - or a little dot, etc,
Then weight the brass as accurately as possible,
then figure out the internal case capacity using the H2O method,
for which brand of brass you want to use,
then figure your load etc.

As for the brass resizing to fit your chamber, I use a RCBS file trim die,
keep adjusting the die down until you get the sizing you want for easy chambering,
then IF needed,
use the size die to just set back the shoulder length to finish the job.

If you can't find a file trim die,
you can get a standard FL die, then cut the die off about 1/16" below the shoulder angle,
you will need a carbide cutter in a lathe or chop saw will also work,
clean up the cut end, polish it smooth with NO burs,
then resize the case body to get a good fit for the chamber.

After several full house loads you will have to set the shoulder back,
to get easier chambering etc.

HTH,

Tia,
Don