Question on seating dies

[Doug Bowser]

I have the opportunity to trade out my RCBS two die FL die sets for the 7.5x55 Swiss, .308 Winchester and .30-06, for the same calibers in the Hornady New Dimension die sets. The New Dimension seating die has a sliding line up shaft that is supposed to keep the bullets straighter when seating. Is this a real advantage in loading accurate highpower rifle ammunition?

Has anyone tried the dies and is there an improvement in the ammunition being straight and concentric?

[runfiverun]

i have a couple of the new dimension sets.
the biggest advantage to them is that hornady can make fewer parts to fit more die sets.
the 308 and 7.5 will be the same seater and i suspect the 0-6 is too just screwed up a bit further.
no advantage or dis advantage really except that the hornadys do stick more with cast boolits.

[versifier]

Here's some food for thought.

Why? Any well made dieset will produce straight and concentric ammo, but that goes with an assumption that your rifle's chamber is cut square and concentric, and many commercial rifles are not. That's probably not a problem with a Swiss rifle. No matter how good the dies are, they are not going to make up for poorly cut chambers. If you have ten commercially produced rifles, odds are that two or three of them have off center or angled chambers, not usually enough to cause problems, but certainly enough to measure. Often it is difficult to ascertain if a concentricity problem (if there is one) originates with the rifle or the dies. You need virgin brass and a second die set to find out. Ammo that is perfectly concentric is not going to have a major impact on accuracy in most production rifles. Bullet, powder, OAL, and brass choice are much bigger factors, then even sizing method and primer choice will still have a greater effect on the accuracy than minor concentricity issues. Are you attempting to solve a problem that may not exist?

Hornady makes decent dies, but RCBS has the best customer service in the known universe. While the Hornady seater may be a little better, the difference is not that great that I would consider trading die sets.

Neck sizing, if it does not cause feeding problems, will make more of a difference in accuracy than changing seaters. What I do (and have done dozens of times) is to order a Collet Neck Sizer set from Lee in addition to the RCBS dies. Neck sizing will usually make more accurate ammo and in every case will increase brass life. The bonus with collet dies as opposed to conventional neck sizers not only the sizer itself but Lee's Dead Length Seater, a better design than both RCBS and Hornady IMO. When I shoot two different bullets in a given cartridge, I just leave one set up for each bullet. If you have a hard kicker, lever, pump, or semi auto, add a Factory Crimp Die at the same time.

Many companies make micrometer seaters that enable you to adjust OAL to a greater degree of precision. Do they produce ammo that is straighter and more concentric? Not in my experience, but they do make the process of discovering how far off the lands is most accurate much quicker and easier. If the brass itself is not concentric, which seater you use is irrelevant.

Then you have to ask yourself: Just how accurate is any given rifle? Can it shoot MOA (is it capable)? Most production rifles today cannot, though things are geting a bit better. Sad but true. If it can't, then fancy tooling designed to help the most accurate rifles squeeze just a tad smaller group isn't going to do anything except possibly boost your confidence. If your Swiss is a K31, it is capable of better than MOA (I have never seen one that wasn't) with its favorite bullets. With production rifles it is more often than not a roll of the dice. More than once I have seen guys drop well over $1G for a rifle that couldn't do 2MOA. That's not necessarily a serious disadvantage in a big game rifle, but it makes for a pretty much useless varmint rifle out beyond 200yds. One could (and I have) spend months testing dozens of bullets and powders trying to come up with a decently accurate load before admitting that the rifle is the problem. OTOH, if I have a rifle I know to be capable of subMOA, maybe halfMOA, or even better, I have been known to go to extremes trying to tweak "the load" until I have exhausted all possible tricks and techniques. But I don't come on a rifle that accurate very often. I am not talking about bench rest tools and techniques, just very careful attention to every little basic detail.

[flutedchamber]

I am not a fan of Hornady dies at all. More hype than anything in my experience. With your RCBS dies just seat the bullet a bit (1/16 or so) and give the case a half a turn and finish the seating. A good investment is a concentricity gauge. That will show you if your rounds are up to the task, no matter what brand dies you use...and the results often will surprise you.

[TCPSTLSHTR]

Full length sizing or neck sizing... I guess it would depend of he rifle being used. If you have a break over single shot rifle for example with no camming action from a bolt, a neck sized round may not chamber easily..Depends on the chamber, headspace, shoulder of the cartridge, OAL etc.

And.... there may be other things as well...

Later

[Tom W.]

Get the RCBS or Redding dies and the Hornady Locking rings...

[M700P]

I use JLC Precision dies, custom made by Jim Carstensen for my Remington M700 in .308 cal. It is a factory rifle and not a Bench rest but it is sold as a law enforcement tactical weapon.

Reason being is, if you have dies made specifically for the rifle you are shooting you have a greater chance accomplishing it's full potential. Component selection and attention to detail combined with a good chronograph also plays a major roll. Understanding what your rifle is telling you IMO is the biggest factor and needs to be mastered to fully get everything that particular rifle has. If I can't achieve satisfaction then I just sell them and move on!

[1Shirt]

As long as they load to your satisfaction and to your acceptable level of accuracy, I would stay with what you have. I have dies from about 8-10 different mfg, some no longer in business like Herters, and Bear. I can usually get MOA from all of them if the rifles are capable, I have a good day, and the load is right.
1Shirt!