Which 6mm in long action Remington 700? Quality Brass is issue...

[Fiftydriver]

I've always thought, if there are two cases that are just begging to be improved, it's the Rem 6mm and 220Swift!!

Thanks for measuring that.

Those two and the 257 Roberts really jump up in performance with improving them. The 22-250 is another one that really gains a lot of performance.

Improving the 308 based family really does not add up to a lot of performance gains. The 06 family does pretty good but that's mainly do to the longer length then anything else.

Most modern belted magnums are a waste of time to improve as are all the current rimless magnums unless you do some dramatic changes such as shoulder position relocating or something like that.

 

[B23]

Kirby, Quickload shows the 220 Swift having 47 grains water case capacity and the 220 Swift Improved holding 57. Now I know the Swift case has a lot of taper but does it really pick up that much when it's Improved??? That just seems like a lot for a case that size.

 

[Trickymissfit]

Those two and the 257 Roberts really jump up in performance with improving them. The 22-250 is another one that really gains a lot of performance.

Improving the 308 based family really does not add up to a lot of performance gains. The 06 family does pretty good but that's mainly do to the longer length then anything else.

Most modern belted magnums are a waste of time to improve as are all the current rimless magnums unless you do some dramatic changes such as shoulder position relocating or something like that.

awhile back somebody made a post asking what was Ackley's best improved case designs. I said the 7x57AI right away, as he often said it was his favorite. Yet it wasn't the best! It was the little .250AI. I'd completely forgot all about that little round, and it sure is an over achiever. On the other hand I've long felt the 7x57AI necked up to 30 caliber would have been a fantastic round.
gary

 

[cdherman]

OK, I have been trying to read as much as possible about the 6mm-284. The Lapua brass very much attracts me.

But along the way, I've discovered a number of basic 6mm issues that trouble me:

For instance, the Berger 6mm 115 VLD Hunting bullet has a BC of .545 The .264 bullet in 130 gr has a BC of .552

Now, since I am concerned about terminal energy as well as trajectory, the 130gr 6.5mm slug has some superior features as well. Driving the 6mm 115 enough faster to overcome the superior BC of the 6mm 130, and added ft/lbs from weight seems a stretch.

I've not realty been able to narrow down just what sort of velocity one can get out of a 6mm-284 with the 115s, so that has hampered my comparison.

But at the end of the day, I have begun to wonder why not just stick with 6.5x284. Lapua brass, standardized cartridge, correct headstamp......

And the 6mm-284 pretty much HAS to burn barrels faster than the 6.5x284, which itself is noted to be hard on the barrels.....

Geeezzee .... I'm back to where I started. Chasing my tail....

But in all honestly, I think what I am discerning is that 6mm might be good long ranger caliber for bench rest, for metallic silhouettes, and varmint size game. But when you start drawing a line, at say 1000 ft/lbs of energy as a necessary attribute to kill an animal sized like a deer, then the 6.5mm is going to spank the 6mm. The 6mm has to be driven very fast to get a long way out there, with that kind of energy.

If I want a 6mm, I should recognize that its just not an optimal LONG RANGE cartridge FOR DEER, if that's what I want. Now, if I want to build a light kicking, fine shooting gun for deer out to 400 yards, then I should just go with .243 Win and be done....

 

[Trickymissfit]

OK, I have been trying to read as much as possible about the 6mm-284. The Lapua brass very much attracts me.

But along the way, I've discovered a number of basic 6mm issues that trouble me:

For instance, the Berger 6mm 115 VLD Hunting bullet has a BC of .545 The .264 bullet in 130 gr has a BC of .552

Now, since I am concerned about terminal energy as well as trajectory, the 130gr 6.5mm slug has some superior features as well. Driving the 6mm 115 enough faster to overcome the superior BC of the 6mm 130, and added ft/lbs from weight seems a stretch.

I've not realty been able to narrow down just what sort of velocity one can get out of a 6mm-284 with the 115s, so that has hampered my comparison.

But at the end of the day, I have begun to wonder why not just stick with 6.5x284. Lapua brass, standardized cartridge, correct headstamp......

And the 6mm-284 pretty much HAS to burn barrels faster than the 6.5x284, which itself is noted to be hard on the barrels.....

Geeezzee .... I'm back to where I started. Chasing my tail....

But in all honestly, I think what I am discerning is that 6mm might be good long ranger caliber for bench rest, for metallic silhouettes, and varmint size game. But when you start drawing a line, at say 1000 ft/lbs of energy as a necessary attribute to kill an animal sized like a deer, then the 6.5mm is going to spank the 6mm. The 6mm has to be driven very fast to get a long way out there, with that kind of energy.

If I want a 6mm, I should recognize that its just not an optimal LONG RANGE cartridge FOR DEER, if that's what I want. Now, if I want to build a light kicking, fine shooting gun for deer out to 400 yards, then I should just go with .243 Win and be done....

There are some guys on the Accurate Shooter board experimenting with the .257AI case necked upto 6.5. They are shooting 140 grain bullets at very long range (about 1000 yards) with some very good results. One guy posted his load data, and said he was seeing 2950 fps with no pressure signs. Cases were formed from standard .257 brass, and the reamer is from Dave Kiff. Of course there is the 6.5x57 improved case design that is slightly larger in volume, but also harder to come by. With .257 case, you can buy a bushing die for the .257AI for starters, and ream the neck of a Forster .257AI seater. The standard Forster .257AI die could even have the neck honed out about .010" to get a full length die. Of course if there was a source for .257AI brass, you'd be way ahead in the game plan.
gary

 

[Trickymissfit]

OK, I have been trying to read as much as possible about the 6mm-284. The Lapua brass very much attracts me.

But along the way, I've discovered a number of basic 6mm issues that trouble me:

For instance, the Berger 6mm 115 VLD Hunting bullet has a BC of .545 The .264 bullet in 130 gr has a BC of .552

Now, since I am concerned about terminal energy as well as trajectory, the 130gr 6.5mm slug has some superior features as well. Driving the 6mm 115 enough faster to overcome the superior BC of the 6mm 130, and added ft/lbs from weight seems a stretch.

I've not realty been able to narrow down just what sort of velocity one can get out of a 6mm-284 with the 115s, so that has hampered my comparison.

But at the end of the day, I have begun to wonder why not just stick with 6.5x284. Lapua brass, standardized cartridge, correct headstamp......

And the 6mm-284 pretty much HAS to burn barrels faster than the 6.5x284, which itself is noted to be hard on the barrels.....

Geeezzee .... I'm back to where I started. Chasing my tail....

But in all honestly, I think what I am discerning is that 6mm might be good long ranger caliber for bench rest, for metallic silhouettes, and varmint size game. But when you start drawing a line, at say 1000 ft/lbs of energy as a necessary attribute to kill an animal sized like a deer, then the 6.5mm is going to spank the 6mm. The 6mm has to be driven very fast to get a long way out there, with that kind of energy.

If I want a 6mm, I should recognize that its just not an optimal LONG RANGE cartridge FOR DEER, if that's what I want. Now, if I want to build a light kicking, fine shooting gun for deer out to 400 yards, then I should just go with .243 Win and be done....

xyz

 

[cdherman]

There are some guys on the Accurate Shooter board experimenting with the .257AI case necked upto 6.5. They are shooting 140 grain bullets at very long range (about 1000 yards) with some very good results. One guy posted his load data, and said he was seeing 2950 fps with no pressure signs. Cases were formed from standard .257 brass, and the reamer is from Dave Kiff. Of course there is the 6.5x57 improved case design that is slightly larger in volume, but also harder to come by. With .257 case, you can buy a bushing die for the .257AI for starters, and ream the neck of a Forster .257AI seater. The standard Forster .257AI die could even have the neck honed out about .010" to get a full length die. Of course if there was a source for .257AI brass, you'd be way ahead in the game plan.
gary

There sort of is a source for quality brass for 257 Roberts -- I think RWS and Norma make 7x57 which is the parent cartridge. And I think there might be a 6.5x57 that someone makes (RWS?). Both of those sources should be decent. Seems Like a 6.5 Roberts AI is really just a 6.5x57 Mauser AI.....

I dunno -- There is no perfect 6mm or for that matter any caliber...

I wonder if anyone has ever necked down a 6.5x55 swede to 6mm and blown it out AI fashion? That would be a source for good brass and lots of case capacity that would also take advantage of a long action as well, for long bullet placement.

 

[Edd]

You are making this way too complicated.

With your donor action, there is no need to consider anything other than something based on an 06 size case.

Since you want Lapua brass and the only version they make is a 30-06, that part is done.

All you have to do is decide what diameter bullet you want.

Don't forget that a 338-06 is one of the most efficient cartridges on the planet.

 

[Sully2]

Just go with a straight 6mm Rem ( .244 Rem) in that rifle. It will do all you expect a 6mm to do for you.

 

[Outlaw6.0]

OK, I have been trying to read as much as possible about the 6mm-284. The Lapua brass very much attracts me.

But along the way, I've discovered a number of basic 6mm issues that trouble me:

For instance, the Berger 6mm 115 VLD Hunting bullet has a BC of .545 The .264 bullet in 130 gr has a BC of .552

Now, since I am concerned about terminal energy as well as trajectory, the 130gr 6.5mm slug has some superior features as well. Driving the 6mm 115 enough faster to overcome the superior BC of the 6mm 130, and added ft/lbs from weight seems a stretch.

I've not realty been able to narrow down just what sort of velocity one can get out of a 6mm-284 with the 115s, so that has hampered my comparison.

But at the end of the day, I have begun to wonder why not just stick with 6.5x284. Lapua brass, standardized cartridge, correct headstamp......

And the 6mm-284 pretty much HAS to burn barrels faster than the 6.5x284, which itself is noted to be hard on the barrels.....

Geeezzee .... I'm back to where I started. Chasing my tail....

But in all honestly, I think what I am discerning is that 6mm might be good long ranger caliber for bench rest, for metallic silhouettes, and varmint size game. But when you start drawing a line, at say 1000 ft/lbs of energy as a necessary attribute to kill an animal sized like a deer, then the 6.5mm is going to spank the 6mm. The 6mm has to be driven very fast to get a long way out there, with that kind of energy.

If I want a 6mm, I should recognize that its just not an optimal LONG RANGE cartridge FOR DEER, if that's what I want. Now, if I want to build a light kicking, fine shooting gun for deer out to 400 yards, then I should just go with .243 Win and be done....

Lets see if I can muddy the waters some. You're welcome.

Speed & BC:
The 6x284 can & will run 3500fps with 105-107 bullets, in the 3300-ish are with the 115 variety. Berger's 115 is not optimal, I believe the 105 Hybrid is at or near that BC. The 115grn DTAC runs a .585 BC, the 117 Matrix VLD is touted at just over that. Couple a near .600 bc at 3200-3300fps & you a whole different level of performance.

The 6.5x284 will run the 140's (.616 BC) at 2900-ish, I'm GUESSING the 130's up near 3100fps.

Both are crazy accurate & BOTH have 1000yd world records under their belt.

Barrel Life:
The 6x284 will in fact torch the throat faster than the 6.5. By how much is dependent upon how you use/abuse it.

Critters at Distance:
Even though, ballistically, the 6mm stomps the monkey snot out of the 6.5 at pretty much any distance as far as drop/drift are concerned; after the 800 yard or so range, I have to take the added Mass & Cross Sectional Area of the 6.5mm.


t

 

[MontanaRifleman]

Lets see if I can muddy the waters some. You're welcome.

Speed & BC:
The 6x284 can & will run 3500fps with 105-107 bullets, in the 3300-ish are with the 115 variety. Berger's 115 is not optimal, I believe the 105 Hybrid is at or near that BC. The 115grn DTAC runs a .585 BC, the 117 Matrix VLD is touted at just over that. Couple a near .600 bc at 3200-3300fps & you a whole different level of performance.

The 6.5x284 will run the 140's (.616 BC) at 2900-ish, I'm GUESSING the 130's up near 3100fps.

Both are crazy accurate & BOTH have 1000yd world records under their belt.

Barrel Life:
The 6x284 will in fact torch the throat faster than the 6.5. By how much is dependent upon how you use/abuse it.

Critters at Distance:
Even though, ballistically, the 6mm stomps the monkey snot out of the 6.5 at pretty much any distance as far as drop/drift are concerned; after the 800 yard or so range, I have to take the added Mass & Cross Sectional Area of the 6.5mm.


t

Well put Tyler,

The 6.5-284 is an ideal case for RL17. After doing a little research I see some guys getting 3150 ish with the 140's and 17. That said, the 6-284 is a good case for RL33 and some are getting 3500 + with it and the 105's.

I consider my 6-284 more of a recreational, PD, and varmint rifle. I will no doubt take some deer and speed goats with it but my 6.5 WSM will be my primary deer and goat rifle.

Barrel life is a very real issue. The 6-264 is not quite as overbore as the 300 RUM which should get about 1000 rounds of good accuracy if taken care of not shot hot. So under similar conditions the 6-284 "should" get the same or a little more. that adds up to about $.75 per trigger pull after you order a good match barrel and have the smithing done not to mention down time. It is a spendy way to regulate PD's.

Hopefully my nitrided barrel will stretch that out a thousand rounds or more... we will see

To the OP, the 243 and 6.5-284 are both fine cartridges with great Lapua brass available. If you want to shoot the long bullets in the 243, I would do it in a long action.

 

[Swamplord]

Not meaning to derail this thread but ...
where does the 243 WSSM fit into this mess ?
(aside from the obvious brass and action issues )

Ballistically