does anyone have the same chamber?

[jmsarron]

I have just finished building a 6.5 284, rem 700 action, 27” Shilen select match barrel 1-8” twist, HS tactical stock, jewel trigger.

I have just finished prepping 200 lapua cases, I wasn’t very happy with that batch, the flash holes weren’t 100% centered, but I uniformed the flash hole sizes and primer pocket depth and turned the necks. I had to turn the necks .003” to make them uniform, now my loaded case neck diameter is .292”.

My question for anyone who can give me advice is this:…………… My chamber neck diameter is .300”. Is that .008” expansion in by brass a problem? Would it affect accuracy? Will it work harden my brass rapidly, or is .008” acceptable?

 

[Preacher]

.008 clearance seems more like a factory chamber, and it will work your brass a bit, and may or may not effect your accuracy.....
.004 on a side is not a real bad thing, and smaller is better, but I wouldn't loose any sleep over it...

 

[mikecr]

Why does your chamber have a .300 neck?

 

[jmsarron]

6.5 284 is standardized and when you order a reamer for it they send you one with a .299" neck dia,which 90%of the time will blow out and extra .001"). I didn't think that was going to be a problem considering lapua brass had i loaded diameter of .296", or so i thought... The loaded brass was .294" + or - .002"! buy the time i made them all uniform the diameter was .292".

I'm thinking of getting different brass with thicker neck walls and staring over, befor wearing out the barrel with unnecessary load development. What a shame, we all know how long it takes to PREP NEW BRASS.

 

[Shooter32]

When you are going to turn your brass to make it uniform, you dont need to use a standard reamer . I mean if you are going to turn the brass anyway you may as well turn it to fit a tight neck chamber . All of my reamers are speced out with enough room to get a good clean up on the brass . :thumb: