Using 223 Rem data for the 6x45 ?

[brstevns]

In all my years of reloading I have never tried this. Can I use data for the 223 rem. for a 6x45 if using the same weight bullet or a few grains lighter bullet?

[richbug]

I would. 6x45 data is short in supply, lots of heavy bullet 223 data now. No situation I can think of where the larger bore would cause more pressure, as bearing surface is reduced.

[vzerone]

I would. 6x45 data is short in supply, lots of heavy bullet 223 data now. No situation I can think of where the larger bore would cause more pressure, as bearing surface is reduced.

You have that wrong. Larger bore, meaning larger diameter, means more bearing surface. I believe what you meant to say is larger bore increases volume area more as the bullet moves down it, thus pressure decreases faster.

[5Shot]

Take a look here...

http://www.predatormastersforums.com...58#Post1455558

[brstevns]

Gone there a number of times, but some powders I have are not listed but are listed for heavy 223 bullets. I do think you for posting the information.

Take a look here...

http://www.predatormastersforums.com...58#Post1455558

[brstevns]

You have that wrong. Larger bore, meaning larger diameter, means more bearing surface. I believe what you meant to say is larger bore increases volume area more as the bullet moves down it, thus pressure decreases faster.

Then either way, it is safe for me to proceed ?

[5Shot]

Can you compare data from that link I posted to published data for the 223 and see if they correlate?

[Hamish]

Have you got access to 7TCU data?

Have some I can give you. Bullet weight will be the factor.

[Hamish]

6X45 = 6TCU

http://www.lasc.us/RangingShotVirginValley6TCU.htm

http://www.beyond556.com/bboard/foru...reloading-data

[M-Tecs]

You are correct that with bullets of equal weight the larger bore has a shorter bearing area and a larger area in square inches for the gas to push on. This generally reduces pressure but there is no need to extrapolate .223/5.56 data. The top two links should provide you with all the info you need.

Hodgdon is the one I recommend. Lots of 6 x 45 data http://www.hodgdonreloading.com/data/rifle

25 pages worth here https://drive.google.com/file/d/0Bzu...w?pref=2&pli=1

http://www.loaddata.com/members/sear...loading%20Data

https://www.shootersforum.com/wildca...-6-x-45mm.html

http://www.24hourcampfire.com/ubbthr...6x45_load_data

[brstevns]

I did not think the 6x45 and 6TCU used the same data. The 6 tcu could be used if I reduce by 10 % I would think?

6X45 = 6TCU

http://www.lasc.us/RangingShotVirginValley6TCU.htm

http://www.beyond556.com/bboard/foru...reloading-data

[M-Tecs]

They are close but not the same. http://www.handgunhunt.com/tech/t13/

The 6T/CU is practically identical to the older 6mm-223 Remington, also called 6X45mm that was developed in 1965. Initially the 6T/CU had been intended primarily as a metallic silhouette pistol cartridge, whereas the 6mm-223 Remington was developed as a rifle cartridge for benchrest and varmint shooting. The T/CU also differs because the cases have to fireformed to fit the chamber before load development can begin. This will create the sharp 40-degree shoulder with nearly straight case walls. The formed round will look very much like those created by Parker O. Ackley back in the 1950's when he would take a case and increase the shoulder angle then virtually eliminate all body taper. This allowed an increase in case capacity as well as velocity. These cases have simply been termed "Ackley Improved." The 6X45 only requires the handloader to run cases through the sizing die to expand the neck; shoulder angle and body taper remain the same.

[brstevns]

Yes I can do that.

Can you compare data from that link I posted to published data for the 223 and see if they correlate?

[Hamish]

I did not think the 6x45 and 6TCU used the same data. The 6 tcu could be used if I reduce by 10 % I would think?

Ok, I think we're going to have go all the way around the board and start over at GO,,,,,,,.

Need to know all pertinent info: platform, intended projectiles, anticipated powders, etc.

Yes, if planning to shoot lead a good place to start is 10% elbow the listed load data for that same weight jacketed bullet.

Real world side note, with the TCU's you might just as well try your intended load when fire forming, I've never perceived any difference in accuracy, recoil, etc, between fire formed loads and subsequent loadings.

Re: my post above ; 6x45 = 6 TCU. There may well be some minor dimensional differences between them necessitating some differentiation in loadings in the upper end, don't have time to look now, but I POSTED THAT ON THE ASSUMPTION THAT YOU WOULD BE LOOKING AT START LOADS, AND I SHOULD NOT HAVE MADE THAT ASSUMPTION.

I apologise.

[MarkP]

Compare data with sectional densities rather than bullet weight.

[brstevns]

No problem, I always use the starting loads and work up.

Ok, I think we're going to have go all the way around the board and start over at GO,,,,,,,.

Need to know all pertinent info: platform, intended projectiles, anticipated powders, etc.

Yes, if planning to shoot lead a good place to start is 10% elbow the listed load data for that same weight jacketed bullet.

Real world side note, with the TCU's you might just as well try your intended load when fire forming, I've never perceived any difference in accuracy, recoil, etc, between fire formed loads and subsequent loadings.

Re: my post above ; 6x45 = 6 TCU. There may well be some minor dimensional differences between them necessitating some differentiation in loadings in the upper end, don't have time to look now, but I POSTED THAT ON THE ASSUMPTION THAT YOU WOULD BE LOOKING AT START LOADS, AND I SHOULD NOT HAVE MADE THAT ASSUMPTION.

I apologise.

[Wayne S]

223 case from base to bottom of neck 1.565, shoulder angle 23*
6 x 47 case from base to bottom of shoulder 1.565, shoulder angle 23*
223 case OAL 44.70 MM
6x47 case OAL 46.99 MM
Speer manuals list 6 x 47 data

[brstevns]

Thanks Guys!

[GrocMax]

Having played with both 6x45 and 6TCU I can tell you they are NOT the same, TCU has considerably more case capacity.

Sectional density is a very good way of trying to equalize, but in a nutshell for equivalent bullet weight 6x45, 6x45AI and 6TCU will take well over a max 223 load, so if you are shooting 55 nosler BT's look at a middle load for 223 same weight bullet/powder that should give you a safe starting point. The 6's will tolerate a step faster powder same bullet weight.

The old 6x47 (222 mag case based) is roughly equivalent to a 6-204, since the 204 Ruger is based off the 222 mag, which has even more case capacity.

My 6TCU will fling a 58g vmax faster than my 223AI will fling a 55, with less case stress.

There is but a minor difference between a 6x45AI and a 6TCU, TCU has a longer neck and a couple other minor differences. A 6x45 or 6x45AI will not chamber in a TCU.

[mfraser264]

Sierra manual #4 - 50th anniversary edition has the data you are looking for, see page #244. Do not use the 6x47 data as it is based on the .222 magnum is much different due to the internal case capacity.