284 Win reamer

sierracharlie338

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Ive decided to start gathering parts for a 284 win build, even found some Lapua brass to start off the build! This will be on a long action.

My question is on reamer specs. Is there a reamer spec already out there that is worth looking at or using? Initially I planned on sending a dummy round in to have one done but figured I should check if anyone was aware of a decent one that already existed.

The goal is to seat 175-180 grain Berger's long so there's plenty of room for powder to run them with plenty of speed. Any help is appreciated.

SC
 
Ive decided to start gathering parts for a 284 win build, even found some Lapua brass to start off the build! This will be on a long action.

My question is on reamer specs. Is there a reamer spec already out there that is worth looking at or using? Initially I planned on sending a dummy round in to have one done but figured I should check if anyone was aware of a decent one that already existed.

The goal is to seat 175-180 grain Berger's long so there's plenty of room for powder to run them with plenty of speed. Any help is appreciated.

SC
I remember Ryan Pierce had mentioned reamer spec that he figured out a long while back for the 284 win. I can't remember the freebore or neck diameter but I think he pretty much got it nailed. You might do a search here on LRH and find that thread.
 
Here is my 284 Win reamer used in a LA Rem :
FB 172, 1 degree 30 min throat angle, .3165" neck which requires turning. I am using a 3.225" OAL.

Lapua brass fed 210M and RL-17

Very happy with the results with 180 Berger hybrid target bullets.
 
Here is my 284 Win reamer used in a LA Rem :
FB 172, 1 degree 30 min throat angle, .3165" neck which requires turning. I am using a 3.225" OAL.

Lapua brass fed 210M and RL-17

Very happy with the results with 180 Berger hybrid target bullets.
Definitely don't want to neck turn but I am curious what speeds you were getting with the 180s.
 
I remember Ryan Pierce had mentioned reamer spec that he figured out a long while back for the 284 win. I can't remember the freebore or neck diameter but I think he pretty much got it nailed. You might do a search here on LRH and find that thread.
I'll do some more digging but didn't find much initially
 
I asked Dave K for a 284 reamer tailored for the 175 Berger Elite Hunter, this is the print he sent me
Screenshot_20210502-161700_Excel.jpg
 
Most accurate load was 50 gr of RL-17 for 2802 fps with the 1 in 7 twist 28" barrel. Did get some faster loads with H4831 and RL-17 but not as accurate.

Just the linked article above. He never used any heavies. He reported what his 1 in 9 twist 21" barrel did with the 139 LRX, 145 LRX and 160 deep curl.

As to turning the necks.... Factory winchester brass wall thickness varies quite a bit to get more consistent neck tension/bullet release it is necessary to turn them.( I have hundreds of pieces of the win brass) If you could get your hands on some Lapua then by all means go with a no turn neck.
 
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I just had one built with a standard reamer but the throat extended to fit the 175 base at the neck shoulder junction.

I need to start load development soon then will get back with numbers. Im hopeful the 4831 is good or R26
 
For a no turn neck shooting 180 Hybrids the standard is .320" neck/.225-.250" freebore. My .284 no turn reamer has .225" freebore for the 180/184 Hybrids but, if I were to have it reground, I would go with a .250" freebore so I could have the base of the bullet a closer to the base of the neck. For a hunting gun I would go .225" so you could still run shorter bullets and have plenty of bearing surface in the neck. A friend of mine just measured a new Lapua .284 case with a 180 hybrid seated and the loaded neck diameter was .315"; this gives 0.005" total clearance which is perfect for the .284 Win.
 
For me I recently built a 284 win on a long action. Used a standard no turn reamer which McGowen precision has. I loaded up three 197 SMK's to optimal length and to them seat dummy rounds on the lands. Realize though when you do this it makes anything less than 180 GT bullets iffy, unless you go to a monolithic bullet. Which I was fine with. Any hoot 180's load out at 3.269 197's 3.393. 28" McGowen 1-8 twist. About 15ths off lands. Getting 2,930 out of 180,s 2,875 out of 185's. And 2,745 out of the 197's
 
Wow! That's a fast barrel!
My Criterion has .319 no-turn neck with .220 freebore. I'm not near my load room to give exact measurements but Berger 180 Hybrid Target seated 20K off keeps bearing surface just above neck-shoulder junction and still gives full neck area contact.
I like it that way for accuracy.

My 2 cents!
 
Wow! That's a fast barrel!
My Criterion has .319 no-turn neck with .220 freebore. I'm not near my load room to give exact measurements but Berger 180 Hybrid Target seated 20K off keeps bearing surface just above neck-shoulder junction and still gives full neck area contact.
I like it that way for accuracy.

My 2 cents!
I'm pretty sure I can picture what you are describing but would you mind sharing a pic of a seated bullet with a loose bullet next to it when you get a chance?
 
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