Seating problems...

[MT257]

I went to go find the length of a Berger VLD touches the lands in my 300 win mag this evening and checked to make sure the empty case chambered first. It did. I kept seating the bullet further and further, I couldnt close my bolt or was I remotely close to being able to close my bolt during the process. I pulled the bullet out of the case and now I cant even chamber the piece of brass. I am not real sure where to start to figure out this problem.

 

[SidecarFlip]

First thing you need to do is look inside to see what's in there.

For that you'll need a borescope.

You can spend 700 bucks for a Gradient Lens Hawkeye or go to Harbor Freight and get yourself an 89 buck inspection camera. Thats what I use.

It has a led light built into the end and while it won't fit down your bore (It will fit down a 50 cal bore), it will allow you to inspect the receiver, the barrel face and where the cartridge brass meets the chamber plus it allows you to inspect the lands.

The light is bright enough and the resolution is good enough to see at least halfwau down the barrel with no issue.

It's a nice tool to have plus you can plug a monitor into it if you want a BIG picture.

I had the exact same issue with one of my sticks. Turned out ther was a small burr at the beginning of the lands. That was hanging the pill and pulling it out of the case. I used a Tungsten Carbide scriber and worked it out (with the cam inside so I could see it clearly. After that, I loaded to the lands and got my LL measurement, no issue.

You have some obstruction inside and the only way to see it is look inside.

You should be able to long load a dummy round (I use a bushing die with a bushing that will allow pill movement without too much resistance load it in, close the bolt (the bolt will push the pill to the lands (an d the pill will 'engrave the lands, you'll be able to see it on the ogive near the base).

Retract the bolt and then measure your LL distance using the appropriate gage and a set of calipers. Never neasure from the tip of the pill to the base of the brass, always measure on the ogive with the correct gage. Hornady sells a set or you dan make your own, if you have machining skills. Typically, a 30 caliber uses a 0.040 gage.

Do the seat to lands at least 5 times and when you get a donsistent measurement, thats the one you go with. I do mine 7 times and add them all and divide by 7 for the average,

I use mine all the time to insure I've cleaned the bores of all copper fouling. It's amazing what BTE can doo (not a plug). I can take a fouled bore, clean it with BTE, inspect it with the cam and shes as clean as a whistle....

Good for other things like looking inside a die to make sure it's not scored ot looking in your dar engine to see whats inside....lol

 

[LoneTraveler]

The case fit the chamber, Now case won't fit with bullet removed. One of 3 things would cause the case change size somewhere . 1. Case neck to tight to allow bullet to be seated without shoving the shoulder on the case out . 2. If the case neck was annealed, The neck was annealed to far down and softened the shoulder to much. 3. If the seating die has crimping capability. The die is adjusted to deep in the press, This will allow the case neck to hit the crimping ring in the die and if the bullet does not have a canular for the case neck to crimp in. All 3 of these will shove the shoulder down into the body of the case and the front edge of the body at the junction with the shoulder swells out. Good Luck in finding the problem.

 

[EddieHarren]

Start over with a new piece of brass.

 

[MT257]

So I went back and started all the way over. And resized everything. I eliminated the problem with resizing, the last time I sized my press had no cam over and this summer I upgraded to the rock chucker supreme. After resizing I made a dummy round and no longer have an issue.

 

[SidecarFlip]

Obviously then, you are not using a bushing die, but rather a stock, fixed chamber die set. that sets the shoulder datum to Sammi spec, which, may or may not be optimum for your firearm....

I would never 'cam over' my press (I have a Rock Chucker as well) when sizing brass because I use a bushing dies, in my case John Whidden die sets.

With a bushing die, the die base is shortened so that you can set the shoulder datum for the best possible chambering scenario (bump back). I typically bump my shoulders 0.002-0.003 with every resize (always FL).

I also remove the expander ball from it's stem and only reduce the neck to a dimension that allows proper fit for a pill. Why expand a neck thats already been expanded by propellant ignition with an expander ball? the more you work brass, the faster it workhardens. I'd rather work it once, versus twice with every resize.

I chuck my fixed chamber dies (I have some) in a jig and grind a couple thousands off the base (you can do that by hand if, you are careful and maintain a square edge on the base).... That allows a fixed chamber die to become a bump die and be capable of setting the shoulder datum back for easier chambering and on long jumps, less brass transfer to the bolt face.

Fixed chamber dies ground to Sammi specs, in my opinion, are too constraining to allow fine tuning of a round as it pertains to a particular firearm. Standard, fixed chamber dies are fine when starting out but for tuning a load for best performance, a fixed chamber, cam over die is much less than ideal.

An added benefit of bumping the shoulder datum back is your cases will grow much less. I rarely trim cases. Usually, by the time they grow to the 0.015 Sammi recommended long length, they wind up in the scrap can anyway because the pockets are shot or in the case of a 300WM, they are starting to seperate at the belt.

 

[SidecarFlip]

Still a good odea to buy the camera from HF... Or, if you have a fat wallet, a Hawkeye....

Do you really know how well you are removing fouling from the tube after you shoot it and do you really know if the lands are becoming eroded (in the case of a 300WM erision is a real and present possibility).

Without being able to look inside, it's all conjecture on your part.

 

[LoneTraveler]

MT257 Glad you got the cases to fit back in your rifle. Go back to my first post. Sounds like your sizing die I doing its job. Put an empty case in your shell holder and run the ram to the top. Then slowly screw the seating die into the press when you feel the slightest resistance back the die back about 1/4 of a turn and lock the nut down. This will keep you form hitting the crimp section of the die. I have measured cases and found an 8 or ten thousands bulge where the shoulder meets the body and that is all it takes to cause a real problem. Good Luck and Happy Loading.