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-   -   What am I doing wrong here? (http://forums.thecmp.org/showthread.php?t=226415)

Homey B 04-04-2018 12:00 PM

What am I doing wrong here?
 
Here's a fun tale for you. Not so fun for me, though.

I am reloading 30-06 for competition. I am using LC69 brass, once fired by me out of a Garand. Brass prep is all done on a single-stage press - resize, deprime, swage out crimp. I use a Redding Full Length sizing die, with the base of the die just touching the shell holder. Then, the brass gets trimmed if necessary, and it's cleaned for reloading.

I'm using the Hornady 110 grain Varmint SP heads over IMR 4895. Loaded to a COAL of 3.09 inches, well below the maximum length.

At the end of the exercise, the rounds are all within spec, according to my calipers. They look awesome.

Took them out to shoot them in a "freshly rebuilt by the CMP" 1903A3. And I struggle to get the bolt to close on them. One of them jams so tight that I need a hand to get the bolt open again. I ask myself "wtf?"

I bought a Lyman case gauge, one that measures the round against the datum point, on the advise of another shooter at the club. And my load plops in nice and clean, right at the correct length marks. The neck of the case is below the "too long" line, the headstamp is at the correct depth, the neck and bullet go through the hole at the top. No rubbing, but no excessive play between the round and the gauge.

Is the gauge bad? Idunno, maybe? For comparison, I drop in a factory M2 ball round that I got from the CMP (LC brass, not the Greek HXP). Call that a known size, right? That round falls into the gauge perfectly, too! Not too long, not too short, no wiggle room, etc.

Now I'm confused. I chamber that piece of M2 ammo, and the bolt closes easily. The chamber is happy to take the Government M2, but not the reload.

If both rounds (my reloads and the factory M2) fit in the gauge and come out where they should, then why does one chamber and the other not? Have I completely missed something? I've never had this issue with my 223 reloads (for Service Rifle), so I am confused as to what is actually going on here.

Can anyone out there offer some guidance as to what I might be overlooking?

Thanks in advance!

JimF 04-04-2018 01:03 PM

Any “burnish” marks on your reloaded cartridges?

Sounds like they must be binding against the rifle chamber somewhere.

Maybe against the bolt face?

Slightly high primer?

Twinson 04-04-2018 01:12 PM

Your chamber might be smaller than the case gauge. Take a resized piece of brass and chamber it like a head space gauge (stripped bolt and no extractor, clean dry chamber). If the bolt handle won't close on the resized brass, you found your answer. Your chamber might be at min. spec and your resized brass might be larger then that but still within the case spec.

nf1e 04-04-2018 01:12 PM

Been there, done that.
Just ran through the same situation with Redding FL die for 6.5 Creedmoor. Same problem chambering. Found that the Redding die doesn't size it enough.
You might want to think about a Sheridan cartridge guage, the split variety. Lets you see exactly what is going on with your load. The Wilson only shows headspace and not actually the chamber diameter.
I tried one of my RCBS sizing dies and no problems.
I ended up ordering a Redding body die and that works fine where the FL sucked.
Just when we think things are working, a new fly is found in the ointment.

Semper Fi
Art

ceresco 04-04-2018 01:36 PM

Simple. Forget the gauges for now, it is your chamber that counts. Take some of your brass and full length size a couple the same as before, then screw the die down a guarter turn and size a couple more. Try them in your chamber and you will probably see that your problem is solved. BTW.. you should always check sized brass in the rifle before you complete the loading process. Good Shooting. ...

rcolarco 04-04-2018 01:59 PM

I had the same situation. The solution for me was a small-base resizing die. It might work for you. Might not. Without being able to examine the rifle and ammo, no way to tell.

If you are getting resistance at the base when you try to chamber a freshly-resized case, the small base die may work. Try to borrow one and see.

Garands have generous chambers, and do not support the cartridge base well at all. You may be getting some base swelling that the standard resizing die is not taking out.

GarandGrabber 04-04-2018 02:17 PM

Quote:

Originally Posted by ceresco (Post 1704578)
Simple. Forget the gauges for now, it is your chamber that counts. Take some of your brass and full length size a couple the same as before, then screw the die down a guarter turn and size a couple more. Try them in your chamber and you will probably see that your problem is solved. BTW.. you should always check sized brass in the rifle before you complete the loading process. Good Shooting. ...

This is exactly what I would check..have dealt with the same issue and just a quarter to a half turn and ..viola..fixed

bigedp51 04-04-2018 04:30 PM

You fired the cases in a M1 Garand and now after sizing they do not chamber in a 03-A3 bolt action.

I buy bulk once fired Lake City 7.62 and 5.56 cases and size them the first time using a small base die.

The problem you are having is caused by brass spring back after full length resizing. It could be by the shoulder location or case diameter. A small base die will size the case to minimum SAAMI dimensions, meaning .002 to .003 smaller in diameter and bump the shoulder back further than a standard die.

Before I would buy a small base die I would adjust the die down 1/8 to 1/4 of a turn past contact with the shell holder. And when you size the cases pause at the top of the ram stroke for 4 or 5 seconds. Pausing will greatly reduce brass spring back with the case trying to return to its fired diameter.

I use JP Enterprise case gauges on my once fired brass because these case gauges are made from finish chamber reamers and closer to SAMMI minimum dimensions.

Below a Wilson, Dillon and JP Enterprise case gauges and as you can see the JP Enterprise gauge is smaller in diameter. Meaning if the resized case will fit in the JP Enterprise gauge it will fit in any chamber.

https://i.imgur.com/KSB3ZvP.jpg

ceresco 04-04-2018 05:34 PM

LC 69 M2 is a low pressure round compared to HXP or commercial loads. It will not fully obturate when fired. It is highly unlikely that the base/web area is blown out from the OP'S initial firing, regardless of whether he fired it in a M1 or bolt rifle. I reloaded an entire 50cal can of once fired LC M2 using a neck sizing die and all but a few chambered easily-- not recommended, just FYI. The OP in all likelihood does not need a small base die or a different gauge--just a die adjustment. It is true that extra lube, a pause or double hit during FL resizing seems to help. Good Shooting. ...

lapriester 04-04-2018 05:34 PM

Your chamber is probably very tight. Have you checked headspace on the A3? If the prepped brass is measuring correctly in the case gauge the chamber is definitely the culprit. There should be no reason whatsoever that you need to size brass for a bolt gun in a small base die after being shot in a Garand. If it fits the gauge as you say it does it should easily chamber in any bolt gun you load it for unless the chamber isn't headspaced properly. I have 6 different 30-06 bolt guns and none of them will fail to chamber any brass I've shot in any other rifle, Garand or otherwise, once that brass is full length sized. The only problem I sometimes have is that brass rims damaged by the Garand cause it to not fit all the way into the case gauge but, even so, that brass will still load easily in my bolt guns. In fact, brass that has that bad a rim damage I usually set aside specifically FOR future bolt gun loading.


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