Need advice on 6BRX midrange project

[chuckgreen]

I need some guidance on selecting the best 6mm bullet, twist rate and throat for a new project.

I'm planning to start shooting a local prarie dog silhouette match each month. As I am basically a 1K BR guy I don't know much about choosing light bullets for shorter ranges.

This match has a light class and a heavy class. The class is determined not by the weight of the equipment but by the bullet weight and case capacity of the round. I've got the heavy class covered.

The light class, however, involves shooting at four distances from 200 yards to 385 meters. Max bullet weight is 70 gr and case capacity cannot exceed that of a 22-250. I plan to shoot 6mmBRX.

I have a couple of questions for which I haven't been able to find answers by searching the form.

For this range of distances would it be better to shoot a flat based bullet or a boattail? Any thoughts on bullet choice?

Assuming I'll be shooting a bullet in the 65 to 68 gr range what twist, throat and barrel length would be considered most advantageous at the required distances? Barrel weight is not a limitation. In fact heavier is probably better for this purpose.

I'll soon be ordering a barrel, reamer and bullets specifically for this project so would appreciate any input.

Thanks,

Chuck

Chuck

 

[tightneck]

First, I don't like the cartridge choice. The BRX is too much cartridge...I'd go with the 6PPC. Nothing wrong with a 6BR, but I believe its best used with heavier bullets, like the BRX. I like 13.5 twist barrels with boattail bullets in the 65-68 grain range, and a 14 twist for FB bullets. For the popular double radius bullets being used today,either FB or BT), a throat between zero and .030' is optimum for the PPC.

 

[chuckgreen]

Thanks for your comment. That's helpful.

The reason for the BRX is that I already have a great switchbarrel rifle in this caliber with a 1-8 twist that I plan to use with my regular Berger 108 1K load for the heavy class of this match which involves engaging targets out to 500 meters.

My thinking is to just get a slower twist barrel to use with light bullets in the light class and switch barrels between classes. It only takes me a few minutes to swap. 6PPC would probably be a bit better for the shorter ranges but I don't want to get into another caliber if I can avoid it.

Chuck

 

[MarkS]

Chuck,

A 14 twist would be best for the 65 to 68 gr bullets. Check the throat on you reamer. See if you can seat a 68gr to touch the lands with the long throat. I think you should be able to my BRX with touch with the 68gr.


Mark Schronce

 

[yat3b35]

I've tried the 70gr Sierra hpbt in my 6ppc and didn't like them for 400 to 500 yard groundhog shoots. I prefer the Hammond 68 gr fb bullets. They are very good bullets, if you can get them. http://benchrest.com/hammonds/ He is close to me so it's not a problem.They are longer than the 70gr hpbt by Sierra and a much better bullet. My barrel is a 14 twist and a hummer. Another very good choice would be the Bib 67 gr. fb. Randy Robinett makes some of the best bullets around. http://www.bibullets.com/products and one heck of a good guy to deal with. If you call him be ready to be on the phone for awhile cause he loves to talk. His 67gr wants a 14 twist barrel as well.Sorry I can't be of help as far as free bore requirements, but hope my input helps. John