308 win neck sizing & competition die

[boomer135]

I have been a reloader for 6 years:

I am attempting to up my game with accuracy. ( I believe being a hand loader for long rage you should take every advantage you have to "squeeze" the accuracy out of any rifle.)

Here is the Backstory:

I am running a Savage model 10 PC 20" heavy barrel in a Choate Tactical stock. 1in10 twist.

I have worked up a very accurate load using redding full length sizing die and bullet seating die (the basic Series A die set) with Federal GMM brass/42.5 IMR 4895/ SMK 168 /2.80 OAL /CCI LRP

Its time to toss the brass due to the primer pockets getting a bit loose after 4-5 firings. I am shooting 3/4" groups @ 100 yards.



So here where the questions come in:

Since it's now time to buy brass. I am going to buy the Lapua brass in 308 win.

-Should I only neck size after fire forming the Lapua brass after full length sizing?

-Do I need to get the competition seating die for easier OAL adjustment?

any other info/education will be appreciated.

I will also be doing some testing w/ Varget with the 168 & 175 SMK.

[FLIGHT762]

You can neck only size (N/O) cases, but you will find after about 3-4 firings, you will need to F/L size the cases again since they will start to be difficult to chamber. If you over do it, you'll be beating on your bolt handle after getting a stuck case.

If you properly set your F/L die to only bump the shoulders of the cases back .001"-.002" from your fired cases, you will get long case life as you will with N/O sizing.

You will need to use a bump gauge comparator like the Hornady bump gauge, RCBS precision mic or a similar gauge to get precise measurements of your shoulder bump. This is a better way of setting your F/L die up than just guessing. You can always use your Rifle's chamber as a gauge to adjust your F/L sizing die but it takes some trial and error to get it right. Bump gauges will show you the exact numbers of what will chamber and what will not.

If you want 100% chambering reliability, set up your die right and F/L size every firing.

I occasionally N/O some of my target loads, but I keep very good notes on the ammo container showing how many N/O sizings there have been.

If you haven't bought a N/O die yet, I'd recommend the Lee Collet Die. It will give you very low runout. I use one along with a Redding "Body Die" to make very accurate ammunition.

I do like my Redding Competition mic seater. It makes going back to different seating depths a breeze. If I were to buy another one, I'd buy the Forster mic seater, it's a bit less expensive and will work as well as the Redding. The only downside to the Forster is you can't find one, everyone's out of them.

[boomer135]

makes sense to me. My reason for the comp seating die was adjusting OAL I seem to get a few rounds way out of my tolerance. and the adjustment would be easier.

Although some of the difference may be in the hollow point of the SMK

[Khromo]

...
-Do I need to get the competition seating die for easier OAL adjustment?...

That die will make it quicker to adjust your seating depth.

I think a much bigger advantage is the improvement in bullet-to-bore alignment, due to the sliding sleeve inside the die which helps keep the bullet straight during seating.

I recently found it reduced runout in .260 Rem cartridges by about 40%, very consistently. When I switched to that die from the standard seater, my group sizes in that gun shrank from about 0.70" to just over 0.50".

[Khromo]

makes sense to me. My reason for the comp seating die was adjusting OAL I seem to get a few rounds way out of my tolerance. and the adjustment would be easier.

Although some of the difference may be in the hollow point of the SMK

If you measure those bullets from the base to the tip, you will see where most or all of that variance is coming from. Try using a comparator to measure your loaded rounds from the base of the cartridge to the ogive of the bullets.

http://www.brownells.com/reloading/measuring-tools/bullet-comparator-inserts/hornady-lnl-comparator-set-22-6mm-25-270-7mm-30-cal-prod35659.aspx

That should clear things up!

[boomer135]

I'll pick up some tools mentioned above and try some different parameters to see what works best!

Excellent information! thx

[LynnJr]

If you are wanting to load for accuracy you have to use a comparator to set your seating depth and you need to dial it in to 0.002 max spread.
Most reloaders stop looking for the correct seating depth way too soon.
If your limited in length by a magazine switch to the Berger VLD design bullets which often times like 0.080 or more jump.

[JMP]

-Should I only neck size after fire forming the Lapua brass after full length sizing?

-Do I need to get the competition seating die for easier OAL adjustment?

OP, I use the dual micrometer Redding Comp dies in every cartridge where they make a set. These are the best dies you will find without potentially eeking out a bit better performance with custom made dies.

Yes, it's great practice to neck only if you are shooting through the same chamber. This saves on the life of the brass. Also, you can prep the brass very quickly. With the gold bushing, you'll find that you can prep the brass in one pull without any lubrication. In fact, as long as you didn't dump your brass in the mud, you don't even really need to tumble the brass as the die is not making contact with the inside of your case except for the decapping pin. Also, when you neck only, you will see that the cartridge has very little growth, so you generally need not trim. This is a major convenience that allows you to get out and shoot more rather than spend all your time reloading.

For the competition seater with the micrometer, the reason you get it is actually that it will seat the bullet much more concentrically that cheap dies. The micrometer is just a bonus. The micrometer is really only helpful if you are changing between types of bullets so you need to adjust it.

.308 Winchester is the one cartridge where I do not get Lapua brass as it lacks volume. I shoot my .308 loads compressed, and I opt to get a bit more capacity. For Lapua brass, you will want to get the 336 and 337 bushing. Most other brass uses the 334 or 335 bushing. If you use Winchester brass, you'll probably want the 331 bushing. Since everyone and his brother makes .308 brass, that is one problematic feature--you will probably end up with half a dozen bushings for one caliber.

JMHO, as folks have different styles.

[boomer135]

That makes a lot of sense I just used lapua brass this last time out with my same max load, Not nearly as accurate due to the case volume. I will work up a new load with the new brass using Varget this time. I will pick up a bullet comparator also and start using this to measure. Measuring from the ogive will give me a more true result, and easier to reproduce.

OP, I use the dual micrometer Redding Comp dies in every cartridge where they make a set. These are the best dies you will find without potentially eeking out a bit better performance with custom made dies.

Yes, it's great practice to neck only if you are shooting through the same chamber. This saves on the life of the brass. Also, you can prep the brass very quickly. With the gold bushing, you'll find that you can prep the brass in one pull without any lubrication. In fact, as long as you didn't dump your brass in the mud, you don't even really need to tumble the brass as the die is not making contact with the inside of your case except for the decapping pin. Also, when you neck only, you will see that the cartridge has very little growth, so you generally need not trim. This is a major convenience that allows you to get out and shoot more rather than spend all your time reloading.

For the competition seater with the micrometer, the reason you get it is actually that it will seat the bullet much more concentrically that cheap dies. The micrometer is just a bonus. The micrometer is really only helpful if you are changing between types of bullets so you need to adjust it.

.308 Winchester is the one cartridge where I do not get Lapua brass as it lacks volume. I shoot my .308 loads compressed, and I opt to get a bit more capacity. For Lapua brass, you will want to get the 336 and 337 bushing. Most other brass uses the 334 or 335 bushing. If you use Winchester brass, you'll probably want the 331 bushing. Since everyone and his brother makes .308 brass, that is one problematic feature--you will probably end up with half a dozen bushings for one caliber.

JMHO, as folks have different styles.

[micro911]

For my rifle rounds, I only use Redding or Forster competition micrometer seating die. Different weight bullet have different ogive length and the die makes it easy to adjust, or come back to the previous setting.

I neck size only for the bolt guns. I discard the cartridge cases after about 4-5 loadings. I have plenty of brass and don't want to deal with any possible issues after that amount of reloading.