284win help

[Hard rock]

That's awesome! I too am going with a 22in barrel and a 5in can. I really need to decide on a bullet. So many options out there. It would be nice if a guy could get 10 or 12 count packs of bullets to do testing so you don't end up with a pile of part boxes on the shelf you prob not going to use.

Depending on your decision on bullets Hammer offers sample packs of 15 bullets , but those are monos that you may or may not prefer and they have a multitude of bullet options and designs for your choice of twist rate ,and will advise accordingly.

 

[pointy sticks]

Mine is a .235fb....Touch with the 166gr Atips is 2.500bto......If you need an OAL measurement let me know.

Ya a coal measurement in that would be good. That first reamer I posted I think is like a .233fb so that may work right out if the box.

 

[pointy sticks]

Not everything, I learn new stuff every day at work.

I think it is safe to say the we make more custom variations of the 284 Win than any other reamer.

I would be interested in your opinion on what fb to go with. Also I was advised to maybe go larger at the .200 line from .501 to like .5019 to avoid clickers. You you feel like that could be an issue?

 

[Hard rock]

I would be interested in your opinion on what fb to go with. Also I was advised to maybe go larger at the .200 line from .501 to like .5019 to avoid clickers. You you feel like that could be an issue?

I have the 284 -2 -6.5-284s -and the 25-284 , I haven't had any clickers with any of them .

 

[pointy sticks]

Ok I think I have been looking at this reamer print wrong. Is there no lead in this print? Is it showing 0 free bore and a .217 throat?
@Ray Gross

 

[436]

Short to Mid action 3.25 coal

Go med or longer.

 

[Taylorbok]

Ok I think I have been looking at this reamer print wrong. Is there no lead in this print? Is it showing 0 free bore and a .217 throat?
@Ray Gross

That's a .217 FB. it'll wo
2.180" case length, .016" transition, .217" Free bore.

BTO measurement should be 2.430 to touch the lands. that reamer should work good for you.

 

[pointy sticks]

So the .217 is fb not the throat? Is there no throat measurement then? I noticed the difference when I was comparing your drawing to this one.
@Taylorbok

 

[Justice1327]

Depending on your decision on bullets Hammer offers sample packs of 15 bullets , but those are monos that you may or may not prefer and they have a multitude of bullet options and designs for your choice of twist rate ,and will advise accordingly.

Berger used to offer sample packs as well

 

[Ray Gross]

Ok I think I have been looking at this reamer print wrong. Is there no lead in this print? Is it showing 0 free bore and a .217 throat?
@Ray Gross

There is no freebore. The throat* is all leade. It is actually quite long. An equivelent throat, with a .2845 dia freebore and 1.5 degree leade would have freebore length around .220 +\-. It is hard to know exactly because a bullet will intercept the 47 minute leade differently than it would a 1.5 degree leade. Well, actually you can probably compute it to a few millionths, but when you start throwing in tolerances, it becomes a best guess

The standard 284 Win throat is an example of chamber throat design that was very common until the 80's or so.

Note how the leade starts at .290 diameter. A throat like that is also suitable for lead bullets that may be slightly over diameter.

That doesn't mean it won't shoot well with current bullets, but you will probably have better luck with a throat that includes a cylindrical freebore section to better align and guide the bullet.

*the terminology for the various chamber structures is muddy. SAAMI uses differently worded definitions to define the 'Throat' and 'Leade' as the same thing. We use Leade as they define it, a tapered cone. But we use 'throat' as slang for everything between the end of the chamber neck to where the bullet first intercepts the leade. So 'Throat', as we use it, would include the Transition, Freebore and Leade. On the print you attached, I would say the throat is represented by the .233 A2 length. Others may use the word differently.

 

[tim_w]

My recommendations:

* Barrel: 1:8.5 Twist (Large buffer to std 300k RPM limit. Largest option for bullet choices trad and mono.)

* Chamber Reamer: Freebore + 1°3' (Freebore length to allow longest body bullet to seat above shoulder junc (doughnut zone) with a bit of extra to length allow for seating depth wiggle room. My guess is 0.190"+

* Action: Long Action (3.5"+ = no worries about running into a Max COAL limit)

* Bullet Recommendation: (Based on 150-160 limit) 150BDII & 155HH (+ traditional hunting bullets)

* Blah Blah Blah:
That is a SAAMI Spec Reamer. It's got zero FB and a extreme shallow leade angle of 0°44'33' vs the more traditional precision throats with an actual FB and leade of 1°30'. I have no experience with such a shallow leade angle outside long throated compound angled leades that start ½° then transion to 1°3'-5'+ to full bore. One thing I would question is the rate of leade erosion with such little land material/length.

I personally would not want the std SAAMI throat of zero FB and super shallow leade which is less that ½ a degree angle. For 150-160 bullets to include high BC monos you will likely be in a 0.180"-0.190" FB with a more tradional 1° 30' leade.

If I had to pick just 2 bullets for typical hunting which tends to be much lower vol vs varmint/target where component cost is not as much a priority it would be 150 BDII by Badlands and 155 HH by Hammer. For support look at the long Hammer & Badlands Bullet performance threads.

While you can tend to get away with less twist below 1.5SG for a given bullet usually down to 1.2 plus any or altitude offset it will tend to yaw the bullet more/sooner on impact. Monos IME are less forgiving to going below the 1.5SG depending on design. At 284 W velocities having a bit more twist is only a benefit. I would run a 1:8-8.5 twist. I can not think of a single negative on performance. Even with a MV of 3200fps bullet with 8.5tw RPM is still under 275k well under the generally accepted 300k limit for jacketed bullets.

The 8.5 twist will allow you to run ANY cup-n-core bullet right up to the 195s plus in the 150-180 monos all but the most radical long nosed monos in that weight range. Example would be the 160gr Super Bulldozer II which is listed to need a 1:7 vs the std 150 Bulldozer II which 1:8.5. For Hammers more tangent noses the 8.5tw is good thru 170gr. (They do have a new design line of higher BC bullets that will be released.that is exciting) I hate to be restricted on bullets or where, what temp, vel combo I can use. To me it's always best to keep options open when it comes to general LR hunting setups. Especially when there is no practical downside in this case. Bullet blowup are not an issue for the cartridge bullet barrel specs.

 

[pointy sticks]

Wow tim thanks for that well written post. This tread is really getting some good input. I do run hammers in my 300wm. I would run them in this gun as well for hunting but I was wanting a cheaper option for kids to practice with that's not pushing a $1 a bullet. Problem is I am still in search of a reamer that will work. I have tried to contact 4d reamer rentals about seeing the actual print for the match reamer they have listed but I haven't gotten it yet. It just has a fb listed as .152 but I wanted to look at the drawing to see if it has a cylindrical fb vs the tapered one like in the sammi print. Dose anyone know of anyone else who might rent reamers?
@tim_w

 

[Cbass1019]

That's awesome! I too am going with a 22in barrel and a 5in can. I really need to decide on a bullet. So many options out there. It would be nice if a guy could get 10 or 12 count packs of bullets to do testing so you don't end up with a pile of part boxes on the shelf you prob not going to use.

I'm sure we can help u with some of those left overs

 

[pointy sticks]

I want to thank everyone who gave their input. I went with a 22in 1in8.5 twist with the custom reamer with .152 fb. I will send in dummy rounds to get it throated. Now I need to get some 7mm bullets to make a few dummy rounds up. If anyone has an assortment like 2 of a few different types i could buy that may be helpful. 130-150 monos and 150-175 cup and core.