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lrshooting
11-17-2015, 10:39 PM
When I build my gun, I made the head space so that it just barely closed on a go gauge just to be safe as it was the first one I had done. Im looking for a little more capacity and I was wondering if upping the head space so that it just barely DOESNT close on the no go gauge would be acceptable.

I understand that normally if you FL size every time with more head space, this would shorten case life but my thoughts are to add .001 shims to the die and glue them when I find the correct amount to push the shoulder back slightly. Ive found with some of my hotter loads that they have to be FL sized or they don't chamber well. Maybe it doesn't even make a substantial effect though. I just know im crunching powder if I seat .005 from the lands with less than 42.7 gr of 4064 and 175 smk. I think I start crunching around 42.3 or so

Robinhood
11-17-2015, 11:20 PM
Crunching 4064 is common. Why do you need washers on your die when it has threads and locking collar?

lrshooting
11-17-2015, 11:28 PM
Crunching 4064 is common. Why do you need washers on your die when it has threads and locking collar? Consistency mainly. I cant imagine being able to get as consistent shoulder set backs by relying on the cam over compared to a solid stop that is adjustable using shims of known thickness. Screwing a die on is a common practice from what research ive done, but it seems some prefer the shim stop over relying on a cam that can wear out to perform exactly the same everytime. I dont see that it could actually have that much effect on accuracy either way though.

Im not super new to reloading, but im not expirenced either so maybe I should just using the locking collar. Except Id have to set it again everytime. I use a lee classic and lee dies. Seem good enough for me but they dont have the set screw collar like RCBS

earl39
11-17-2015, 11:53 PM
Just replace your lock rings with Hornady lock rings. They clamp on instead of buggering up the threads like RCBS lock rings do. Love my Lee dies but hate their lock rings.

Robinhood
11-18-2015, 12:14 AM
My big orange press cams over. My lee classic I just modified to cam over. Consistency was the reason.

sixonetonoffun
11-18-2015, 12:49 AM
What brass are ya using? Seems like you should have some room left?

IMR4064 is one powder that loves compressed loads.

Look on Nosler bullets 4064 and 4350 almost always show max loads for the accuracy load.

As long as the case isn't bulging literally. Load a few up measure n note the coal. Leave em standing In a tray overnight.

Check em the next day. If no changes in length load em n shoot em.

If the length has changed pull em n drop the charge a few .1's try it again.

Hodgens shows WW brass 175 smk's imr4064 max is over 46gr. LC or federal might be another story.

If ya want the brass to grow get a bushing neck die or even an inexpensive lee neck die.

Pin Robinhood down for a how to on your press. SharpShooter posted some pix of how he did it.

sharpshooter
11-18-2015, 12:59 AM
Increasing the headspace .003-.004" will gain you the equivalant of {nothing} in capacity. Take a few kernals of powder out and don't worry about it.

lrshooting
11-18-2015, 01:30 AM
What brass are ya using? Seems like you should have some room left?

IMR4064 is one powder that loves compressed loads.

Look on Nosler bullets 4064 and 4350 almost always show max loads for the accuracy load.

As long as the case isn't bulging literally. Load a few up measure n note the coal. Leave em standing In a tray overnight.

Check em the next day. If no changes in length load em n shoot em.

If the length has changed pull em n drop the charge a few .1's try it again.

Hodgens shows WW brass 175 smk's imr4064 max is over 46gr. LC or federal might be another story.

If ya want the brass to grow get a bushing neck die or even an inexpensive lee neck die.

Pin Robinhood down for a how to on your press. SharpShooter posted some pix of how he did it.
Lapua Brass. Thats one reason, but my hornady brass seemed the same way. Ill leave my HS alone then. I dont have accuracy problems, but I just dont like how much crunch I get. Im shooting clover leafs easy at 200 yards with 42.7-43.1 grains of 4064 and sorted 175 SMKs. Im gonna switch to 178 HPBT though due to large variations in bullet base to ogive measurements with the 175 smk. I found that if I sorted the smks by weight and then by ogive, I ended up with more accurate groups. Just a pain though, and I end up with about 10 different sets of bullets.

I really start to get some push back and immediate change in measurements after I near max charge. Only way I think I could help case capacity out much is to get my throat lengthened to seat bullets further out but I need to be able to mag feed for deer hunting so Ill leave it. Id rather run slower velocities and be able to mag feed then have to hand feed with faster velocities.

LongRange
11-18-2015, 09:07 AM
are you using two comparators like this? if not you should be because if you look at the bases of the bullets they vary some will be pretty flat while others will have a hump in the base.

http://i1239.photobucket.com/albums/ff515/LTT-/Mobile%20Uploads/photo-42.jpg (http://s1239.photobucket.com/user/LTT-/media/Mobile%20Uploads/photo-42.jpg.html)

lrshooting
11-18-2015, 09:28 PM
No, Im not. I guess I better get one ordered.

ronswanson
11-18-2015, 09:38 PM
lrshooting, If you just need a little space you could try to get the powder to settle in the case a little by tapping or vibrating the charged case. I have to do that with some Varget loads to avoid crunching. Also, a drop tube might help, but a few taps on the case usually settles the powder enough for me.

lrshooting
11-18-2015, 11:22 PM
lrshooting, If you just need a little space you could try to get the powder to settle in the case a little by tapping or vibrating the charged case. I have to do that with some Varget loads to avoid crunching. Also, a drop tube might help, but a few taps on the case usually settles the powder enough for me.
Thanks. Ive tried that some, but not really to much help. I may have been doing it wrong so Ill experiment a little. Id really like to just find some varget but Im new enough to the reloading game that ive never once seen a can or jug of Varget yet while looking for supplies. I can find tons of 4064 between 2 or 3 stores. BLC2 as well. IMR 4895 is probably next in availability.

orcldba
11-19-2015, 01:32 PM
Increasing the headspace in NOT a good idea. When the round is fired the brass expands and seals the chamber, starting at the case mouth where the brass is the thin. If there is too much headspace then the case head WILL stretch until it hits the face of the bolt. This, after as few as 2 firings is one of the causes for case separations; where the case head plus about 1/4" of the case is extracted and the rest of the case is stuck in the chamber.

a) If you really 'need' more powder space, then go to one of the 'Ackley Improved' rounds; it's the same round, BUT the taper on the case is decreased, the case shoulder is moved forward (and usually at a sharper angle of 40 degrees), and the length of the case neck is shortened.

b) Compressed loads, within reason, are not at all unusual, especially with heavier charges of extruded (stick) powder. You CAN go to a ball powder with the same burn rate and it will PROBABLY not be a compressed load.

c) You can use a longer drop-tube when charging, which will tend to compress the powder from the bottom of the case up. This lessons the 'crunch' some.

d) Shorter bullets will compress the charge less, although compressed charges per-se are not necessarily bad, and I personally like longer bullets as they will as a rule have a higher BC so they don't have the drop at longer ranges.

By the way, IMR4064, and IMR4895 as well as BLC/2 are very good powders for many loads. I prefer H4895 to IMR4895, but that's a personal preference. I've read that there is a difference and that the difference is just in the package: My tests show that there IS a difference, so I keep up to date on charge loads.

LHitchcox
11-19-2015, 01:49 PM
Keep the minimum headspace and adjust your sizer to partial size to extend brass life. The crunching of powder kernels really is not a headspace issue.