Question for those loading jacketed subs.

[dpete]

My question is would you bother trying to create test loads for a OCW test ladder if the only choices for range use were outdoor at 30* or less and out to 100 yards, and an indoor range with 30 yards max?
I have 200 Hornady 225 grain HPBT to use for a new sub load, and IMR 4227 for powder. The rifle is an 8" barrel with suppressor AR15. I will be chronographing everything. How would you go about running an accurate OCW ladder under these confitions if you would at all? The outdoor range presents the cold ambient temperature problem but I could use warm packs and an Igloo chest to maintain the magazine/rounds temp before shooting them in the round robin ladder. The indoor range would allow normal temperatures but at 30 yards would any of the accuracy data be worth anything since 50 yards is my usual distance for testing my Blackout loads?
I'm tossing this out to more experienced sub shooters before I waste anything. Thanks

[bangbangping]

at 30 yards would any of the accuracy data be worth anything

No.



Oh...you want more? I can't speak to temperature since generally it doesn't get that cold where I live. But I can tell you that several of us figured out in the 200 yard challenge that even 50 yards often doesn't tell you what you need to know about a sub load and how it will shoot at 100 or 200. You certainly can rule out high ES problems (and ES is key, regardless of anything else), but that's about it. Personally I no longer do any development work at 50 unless the 100 yard range is packed and I just have to shoot that day. Been lied to by 50 too many times.

[rjacobs]

Dont waste ammo on OCW

trust the chrono...

You arent working with a huge broad range of powder charges. My guess is you can get it done in 50 rounds.

Load em in .1g increments and shoot them across the chrono. Stay subsonic, ensure function and look for low ES and SD and call it done.

[Dr.Phil]

In general, OCW or Ladders are not practical for subsonic loads.
The velocity window is so small that you will be wasting a bunch of time and components.
(When you factor is a testing distance of 30 yards, you can't really get quality data anyway.)

The accuracy sweet spot for subsonic loads is usually on the slow side. (~ 900 fps)
Of course the slower you go, the more drop you have.
(My target velocity is usually around 1050 fps @ sea level, for typical subsonic loads.)

For any OCW or Ladder testing, I favor using max distance.
That provides much more accurate data.
http://www.6mmbr.com/laddertest.html
Jason Baney's technique of using a Sharpie to mark you shots works very well...
(300 yards for supersonic 300 BLK is what I typically use.)

[bangbangping]

Load em in .1g increments and shoot them across the chrono. Stay subsonic, ensure function and look for low ES and SD and call it done.

I guess it depends on what your goals are. Low ES is certainly necessary for long range sub precision, but I have a big spreadsheet of loads saying it ain't sufficient.

[rjacobs]

I guess it depends on what your goals are. Low ES is certainly necessary for long range sub precision, but I have a big spreadsheet of loads saying it ain't sufficient.

I totally agree, but for what he is attempting to do, or at least what I think the OP is attempting to do, reading the chrono should be sufficient.

[tikkablk]

I guess it depends on what your goals are. Low ES is certainly necessary for long range sub precision, but I have a big spreadsheet of loads saying it ain't sufficient.

I totally agree, but for what he is attempting to do, or at least what I think the OP is attempting to do, reading the chrono should be sufficient.

The only jacketed subs I am using is 208gr Amax.
For me I am after low ES for hunting at long range and use a standard .1 increments ladder set over the chrony. I also batch weight the brass and that makes the biggest difference for me as I am using ex mil 556 brass and once that's all used up will probably go with Lapua.

[dpete]

Thanks for the replies.
I haven't loaded anything yet but I thought I would share what I have done in the past and possible plans now. My accurate load using 220 grain Leatherheads is 9.4gr of IMR 4227 and seated to 2.055". Max load for these Hornady 225gr of 4227 in Hornady's 9th ed. is 10.5gr. A favorite load I picked up online was 9.7gr of 4227 with these 225s. I was planning on starting at 10.3gr and working down in .3gr increments which would include both the 9.7gr load and my 9.4gr load and seating them 2.220" which my unmodified Pmags work with. 9.1gr is as low as I was planning to go for the first test loads. Shooting them over the chrono to determine lowest ES and SD of the 5 charge weights I would then take the best charge and load in .1 increments above and below that charge to fine tune.
Should I go lower than 9.1gr with the starting batch or wait to see what kind of velocities I get with the ones I have planned on?
As I understand things, fine tuning the seating depth to improve accuracy would come after the correct powder charge is determined, correct?

[Dolomite_Supafly]

I shoot across the chronograph to find possible accurate loads before shooting for groups. Consistency is key so I work up loads trying to find the one load that has the smallest ES. You will normally find a few along the way. Then I shoot those for groups and tweak as needed.

A chronograph makes life so much easier on those who reload. I lived without one for several years but will never be without one again.

[dpete]

I shoot across the chronograph to find possible accurate loads before shooting for groups. Consistency is key so I work up loads trying to find the one load that has the smallest ES. You will normally find a few along the way. Then I shoot those for groups and tweak as needed.

A chronograph makes life so much easier on those who reload. I lived without one for several years but will never be without one again.

That is what I did with the 220 Leatherheads I loaded in the past. Shot them through the chronograph without caring where they hit to find the lowest ES and SD, then tweaked the load from there to refine it. Accuracy testing came after.
Given that its butt freezing cold up here right now would I be better off waiting until it warms up a bit? I'm thinking waiting until its at least close to 30* or higher to shoot.