6.5 CM case prep Qs

[Michael in California]

Just starting to work on case prep. I haven't found H4350 yet, so it may be a while 'til I actually work on loads.

However, I have chosen some dies and am messing around a bit.

Rifle in question is a RPR. This is my first bolt rifle. Otherwise I've loaded 30-06 for my Garand.

I plan on using once fired Hornady brass and load with 140 gr ELD-M bullets. Basically the same as the factory rounds I'm using now.

I've chosen Forster dies. Bushing Neck bump die for sizing and the standard seater.

Observations...

I don't yet have a way to measure the shoulder, however, the once fired brass easily chambers whether run through the sizer or not. I cannot tell if the die even hits the shoulder when I mark the shoulder with a sharpie (worked well on the garand) The once fired case length is under sized at about 1.912-1.916 which matches my measurements of the unfired factory rounds.

I'm using a .288 bushing since my factory rounds measure .290 even though the SAMMI max spec is .295. I get neck tension such that if I push down real hard on the tip, I can make the bullet move, but otherwise it is well seated.

I'm going to load at 2.825 which is the SAMMI max length as its the longest I an load in the Magpul magazines. Superficially, I've read that the RPR has a lot of free-bore. Also, a test round loaded to 2.825 chambers well. I'll load a test round somewhat longer and verify I'm not near the lands. I really need to measure better though. And buy some AI magazines.

Questions:

Is it common for once fired bolt rifle round to not stretch? This does not match my Garand experience. They needed trimming after one firing. Less after two firings. Not much more experience than that.

Is the .288 bushing right? Seems to hold well and the math is right giving me a .013 neck thickness which matches what I've read. Does it matter that its not near SAMMI Max?

Is loading to SAMMI max length in an RPR likely to be accurate? Do I really need to get longer. Of course, the answer is to go fire 'em, but some advise would be nice.

Does anyone see anything wrong in my process to date?

I'm real anxious to get some powder and start developing a load. But, I need powder and I'm off traveling for a few days.

[LynnJr]

[QUOTE=Michael in California;

Observations...

I don't yet have a way to measure the shoulder, however, the once fired brass easily chambers whether run through the sizer or not. I cannot tell if the die even hits the shoulder when I mark the shoulder with a sharpie (worked well on the garand) The once fired case length is under sized at about 1.912-1.916 which matches my measurements of the unfired factory rounds.

I'm using a .288 bushing since my factory rounds measure .290 even though the SAMMI max spec is .295. I get neck tension such that if I push down real hard on the tip, I can make the bullet move, but otherwise it is well seated.

I'm going to load at 2.825 which is the SAMMI max length as its the longest I an load in the Magpul magazines. Superficially, I've read that the RPR has a lot of free-bore. Also, a test round loaded to 2.825 chambers well. I'll load a test round somewhat longer and verify I'm not near the lands. I really need to measure better though. And buy some AI magazines.

Questions:

Is it common for once fired bolt rifle round to not stretch? This does not match my Garand experience. They needed trimming after one firing. Less after two firings. Not much more experience than that.

Is the .288 bushing right? Seems to hold well and the math is right giving me a .013 neck thickness which matches what I've read. Does it matter that its not near SAMMI Max?

Is loading to SAMMI max length in an RPR likely to be accurate? Do I really need to get longer. Of course, the answer is to go fire 'em, but some advise would be nice.

Does anyone see anything wrong in my process to date?

I'm real anxious to get some powder and start developing a load. But, I need powder and I'm off traveling for a few days.[/QUOTE]


Brass in a bolt action rifle can generally be shot a couple times before it needs full length or shoulder bump sizing.

Measure a loaded round and use a bushing 0.002 - 0.003 smaller so you are good to go on that.

On the length question if you plan on running rounds from the magazine never run them longer than they will feed well. If you are only single feeding the gun load them as long as possible to get your powder charge then seat them deeper until you find best accuracy.

[Michael in California]

Lynn, thanks for the info.

Follow-up. My sizing die has no expander, but I can optionally buy one. At what point, if ever, will I need one.

I've only set up the dies so far. If I have time, I'll size about 100 tomorrow as see how it goes. If not, next weekend as I have business travel coming up.

Maybe I'll have powder by next weekend too.

[rayw1128]

Hey Michael,

I had a Ruger Precision Rifle gen 2 that I sold about a month back. I was loading 140 ELD-M in Hornady brass. Here are some input...

- Sizing - I only neck sized and I remember that I could get about 3 loads without having to bump/full length size. Bold handle would get harder to close at about the 4th load.

- Neck size bushing - I measured the loaded round and got the a bushing that was 1thousand smaller. Saw a youtube video of some guy at Reddings saying that they recommend that the neck size bushing should be .001 smaller.

- Seating length - I had seated my 140's right to the edge of the magazine where the round would barely fit the magazine. I'm sorry that I dont have the OAL anymore as I pulled apart my dummy round after I sold the rifle.

- Expander for sizing die - you might need one in the future if you decide to load brand new brass. I learned this lesson when I bought brand new brass to reload. The mouth of the new brass are not all concentric (some with portions of the mouth being almost dented in, so sizing by neck bushing will not get the dent out). Expander would be needed to push the dents out to form a concentric circle.

Hope that helps!