Freebore on prefit

mtJim

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Looking at getting a prefit in 28 Nosler, and they list the reamer as being for the 195gr Berger - .300FB.
Is this too much freebore as I won't be shooting the 195gr Berger? I'm guessing the monos would jump that far.
 
Freebore is not jump, depending on the weight of the mono you plan to shoot you could use the freebore up pretty easy. Monos are longer than traditional bullets and you don't want to lose case capacity by seating them down in the case. Load up some dummy rounds and have the smith chamber to your dummy rounds. Most prefit makers have no issue with this.

Or if you have done it buy a Uni Throater and do it yourself. I only trashed one $1000 barrel but you live and learn.
 
Mono bullets arent as jump sensitive and lead core. I was jumping hammers and barnes .050 and they shot great, under .5" and my 338 RCM jumps .25 with monos and shoots .5.
 
Mono bullets arent as jump sensitive and lead core. I was jumping hammers and barnes .050 and they shot great, under .5" and my 338 RCM jumps .25 with monos and shoots .5.

This is along the lines of my thinking. Comparing the Berger 195gr at 1.6" long to a Barnes 145gr LRX at 1.42" long, I was curious if the .200 would be too much. Just comparing OALs, aware that the ogive will determine the actual jump. But I know the monos are a lot less sensitive to seating depth and do better with more jump.

Which bullet are you jumping .25?
 
It matters not…
There are MULTIPLE 'jumps' in a barrel that can be tuned, it can be far, like most Weatherby chambers, or it can be in the middle, or close to the rifling and even jammed.
All of my customs have specific freebore lengths for specific bullets, but many bullets can be tuned to utilise those lengths.
I say, just go at it and get it done.
I used to be concerned with jump, I am no longer.

Cheers.
 
This is along the lines of my thinking. Comparing the Berger 195gr at 1.6" long to a Barnes 145gr LRX at 1.42" long, I was curious if the .200 would be too much. Just comparing OALs, aware that the ogive will determine the actual jump. But I know the monos are a lot less sensitive to seating depth and do better with more jump.

Which bullet are you jumping .25?
175 hammer and 185 barnes. Short mag length
 
It matters not…
There are MULTIPLE 'jumps' in a barrel that can be tuned, it can be far, like most Weatherby chambers, or it can be in the middle, or close to the rifling and even jammed.
All of my customs have specific freebore lengths for specific bullets, but many bullets can be tuned to utilise those lengths.
I say, just go at it and get it done.
I used to be concerned with jump, I am no longer.

Cheers.

That's the nudge I needed.
I'll pull the trigger on it.

Thanks
 
I would spend some time with lancetkenyon before I did anything Nosler 28. He's probably close to 50 now doing load dev, mostly 195's but he's also done work with solids.
 
Far better to have too much jump/free bore than too little. Though I guess the uni-throater idea has merit. I have not went there. With a long free bore you can usually find a spot. With a short one, you end up with a bunch of bullet in the case, less powder capacity.

In a perfect world, you know your mag length, what bullet you want to use etc. You send a dummy to the maker and you get a nice 20 thou over dummy bore. In my experience the world is not perfect. Better long than short.
 

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