Help with OCW test

[Torque]

I'm shooting a new 280AI. This is my first time to the range with it. I am doing a standard OCW ladder and want to sew where you guys think I should move forward. I am very new to examining OCW data. So, if you leave advice, please explain your advice so that i can better understand the process.

280ai Peterson brass, new,
160 Barnes TSX,. seated 0.040 off lands
RL16
CCI BR-2 primer
3 rounds per load

Load 1
53.6g
avg velocity: 2789
ES: 18
group size: 0.75"

Load 2
54.0g
avg velocity: 2816
ES: 35
group size: 1.25"

Load 3
54.4g
avg velocity: 2823
ES: 3
group size: 0.89"

Load 4
54.8g
avg velocity: 2848
ES: 22
group size: 1.06"

Load 5
55.2g
avg velocity: 2868
ES: 9
group size: 0.85"

Load 6
55.6g
avg velocity: 2883
ES: 17
group size: 0.59"

Load 7
56.0g
avg velocity: 2923
ES: 15
group size: 0.48"

 

[Mw01313]

If no pressure signs with load 7, load 10 and shoot a group.
Not trying to give you a short answer, but I used to do all the tinkering with small charge changes and seating depth adjustment. I wasted a lot of components and time. (Learned alot though) Link below to the painless method. I assume from the bullet choice this is a hunting rifle. Using the method in that thread has really simplified loading for me.

Painless load development (mine)

Wish I'd found this method earlier. Burned up a lot of components adjusting charges by .1s of a grain and incremental seating depth changes. On my 2nd rifle now. Much easier.

rokslide.com

 

[Torque]

If no pressure signs with load 7, load 10 and shoot a group.
Not trying to give you a short answer, but I used to do all the tinkering with small charge changes and seating depth adjustment. I wasted a lot of components and time. (Learned alot though) Link below to the painless method. I assume from the bullet choice this is a hunting rifle. Using the method in that thread has really simplified loading for me.

Painless load development (mine)

Wish I'd found this method earlier. Burned up a lot of components adjusting charges by .1s of a grain and incremental seating depth changes. On my 2nd rifle now. Much easier.

rokslide.com

No pressure signs of any kind. Thanks!

 

[FLHunter87]

Are you using this as a hunting or target match rifle? The guy that said shoot a 10 round group is a little ridiculous if its a hunting rifle. 3-5 is plenty of data. How often do you shoot more than 2x back to back hunting? I can only count a few myself. What are you after, accuracy or velocity? Everyone is different and sometimes you can't have both pending what your personal preference for accuracy is. If you don't have pressure signs just keep going. Once you hit that, you have the data you need to decide. You can always try more seating tests as well. TSX work when seated deeper. I have met a handful of guys that reload at the shooting range i go to and all have said working a load at 100 yards really doesn't benefit you due to more stabilization of the bullet at 200 yards and you'll know now about the rifle and the load your using. If it's true or not i don't know, but I have seen things on forums saying the same thing. If you're using the TSX, look at the ballistics of the bullet with velocity and as long as your 1600FPS the bullet will do it's job no matter the distance. Don't worry about energy! I have done the same thing you do and your in the right direction. I would also suggest neck tension is the same as that can affect accuracy more than you think. If you end up seating a bullet too deep and pulling it out, I would resize the brass and start over. I have noticed accuracy problems due to that and learned as I go. I use a 6.5 PRC and I only get 2835fps out of my rifle with my load. But I can stack a 5 shot group at 100 and cover with a penny. At 200 yards I'm around 1.25" group but have only shot 200 a couple times now. I use the ABLR so as long as I'm at least 1300fps the bullet will perform. Even at 1k yards I'm good for velocity but I'll never shoot an animal that far. I also load a 243 and the ES is 35. At 100 yards I can stack just like my PRC. At 200 yards it shoots pretty good also, but I don't like the scope magnification is to low so it's hard to see out that far. If you're not really going long range ES And SD you really don't need to worry about as much. Hope my perspective helps.

 

[sndmn11]

I have met a handful of guys that reload at the shooting range i go to and all have said working a load at 100 yards really doesn't benefit you due to more stabilization of the bullet at 200 yards

What cause the bullet to become more stable?

 

[FLHunter87]

What cause the bullet to become more stable?

I'm not sure, I haven't really looked into much because it doesn't really make sense to me. Maybe something to do with spin drift? They explained something but I forgot.

 

[Miflatlander91]

Are you using this as a hunting or target match rifle? The guy that said shoot a 10 round group is a little ridiculous if its a hunting rifle. 3-5 is plenty of data. How often do you shoot more than 2x back to back hunting? I can only count a few myself. What are you after, accuracy or velocity? Everyone is different and sometimes you can't have both pending what your personal preference for accuracy is. If you don't have pressure signs just keep going. Once you hit that, you have the data you need to decide. You can always try more seating tests as well. TSX work when seated deeper. I have met a handful of guys that reload at the shooting range i go to and all have said working a load at 100 yards really doesn't benefit you due to more stabilization of the bullet at 200 yards and you'll know now about the rifle and the load your using. If it's true or not i don't know, but I have seen things on forums saying the same thing. If you're using the TSX, look at the ballistics of the bullet with velocity and as long as your 1600FPS the bullet will do it's job no matter the distance. Don't worry about energy! I have done the same thing you do and your in the right direction. I would also suggest neck tension is the same as that can affect accuracy more than you think. If you end up seating a bullet too deep and pulling it out, I would resize the brass and start over. I have noticed accuracy problems due to that and learned as I go. I use a 6.5 PRC and I only get 2835fps out of my rifle with my load. But I can stack a 5 shot group at 100 and cover with a penny. At 200 yards I'm around 1.25" group but have only shot 200 a couple times now. I use the ABLR so as long as I'm at least 1300fps the bullet will perform. Even at 1k yards I'm good for velocity but I'll never shoot an animal that far. I also load a 243 and the ES is 35. At 100 yards I can stack just like my PRC. At 200 yards it shoots pretty good also, but I don't like the scope magnification is to low so it's hard to see out that far. If you're not really going long range ES And SD you really don't need to worry about as much. Hope my perspective helps.

I’d do a little google searching for “your groups are too small” as far as the 10 round group being ridiculous


Sent from my iPhone using Tapatalk

 

[ResearchinStuff]

Painless method for sure. If you shot all those combos in statistically significant group sizes you'd find they're all the same. Pick one and load a bunch so you can stop wasting components and start working on your field shooting skills.

Equipment versus practice posts and Rifle practice/shooting

This isn’t in response to anyone I particular, but there is an up tick in the amount of “I want a XXXX distance hunting rifle” traffic the last few months. I am getting a lot of questions relating to this, which I do not mind helping, but thought a public post might help answer some questions...

rokslide.com

 

[sndmn11]

I'm not sure, I haven't really looked into much because it doesn't really make sense to me. Maybe something to do with spin drift? They explained something but I forgot.

You don't know why you gave the advice you did, but you have it anyways? Even when it doesn't make sense to you?

@Torque 2920fps is close to max velocity for the cartridge/bullet mass, but I cannot find RL16 data. Load one each at 56.5, 57.0, 57.5 to see where things get stuck, then load the rest a grain or grain and half below that and go shoot.

 

[Muddler]

I believe you need to find the center of each group, and then plot each of those group centers together to find which ones are the closest. Then work up a load/seating depth within that range.

This explains it better

OCW reloading instructions

OCW reloading overview and instructions

www.ocwreloading.com

 

[Mw01313]

Are you using this as a hunting or target match rifle? The guy that said shoot a 10 round group is a little ridiculous if its a hunting rifle. 3-5 is plenty of data. How often do you shoot more than 2x back to back hunting? I can only count a few myself.

The idea of a ten round group has nothing to do with how many times you need to hit an animal in a hunting situation. Although, if you start hitting critters at 1600FPS with a Barnes it may become relevant. Any data is more accurate with more samples.

I'm not sure, I haven't really looked into much because it doesn't really make sense to me. Maybe something to do with spin drift? They explained something but I forgot.

I'm not sure, I haven't really looked into much because it doesn't really make sense to me. Maybe something to do with spin drift? They explained something but I forgot.

Huh?

@Torque 2920fps is close to max velocity for the cartridge/bullet mass, but I cannot find RL16 data. Load one each at 56.5, 57.0, 57.5 to see where things get stuck, then load the rest a grain or grain and half below that and go shoot.

This

 

[Torque]

You don't know why you gave the advice you did, but you have it anyways? Even when it doesn't make sense to you?

@Torque 2920fps is close to max velocity for the cartridge/bullet mass, but I cannot find RL16 data. Load one each at 56.5, 57.0, 57.5 to see where things get stuck, then load the rest a grain or grain and half below that and go shoo

@Torque 2920fps is close to max velocity for the cartridge/bullet mass, but I cannot find RL16 data. Load one each at 56.5, 57.0, 57.5 to see where things get stuck, then load the rest a grain or grain and half below that and go shoot.

I am using Quickload for powder data. I am using Peterson brass and the h20 capacity is below the published norm. 70.4g h20 is what I am measuring. They are all extremely consistent for that measurement. After altering the case dimensions in Quickload, RL 16 and Big Game Hunter are the two powders that looked promising for both burn rate and case capacity. They were not powders I would have expected for that case, but QL was spot on for the velocities. I am seeing zero pressure signs. I am not even seeing flattened primers. Which is great. I stopped loading at what QL said was the top pressure load. I will work up some higher charges and see how those end up. Thank you for the advice.

Information I should have thought to list in my original post:
It is a hunting rifle
Neck tension two thou
Bullets are seated to the bottom of the neck not into the case body, 40 thou off lands
I am more concerned about accuracy than velocity, but both are important.

 

[sndmn11]

I will work up some higher charges and see how those end up. Thank you for the advice.

You just need to do one at each higher powder charge. You could even go higher and just stop when you get sticky in the chamber. The intention there is just to understand and I still confidence that you aren't on the fence and maybe see issues in other conditions.

If it were me, I'd load 10 at 56.0 to shoot a group, and single cartridges above in .5gr to 57.5/58.0 with the intention of living at 56.0.

 

[wind gypsy]

I believe you need to find the center of each group, and then plot each of those group centers together to find which ones are the closest. Then work up a load/seating depth within that range.

This explains it better

OCW reloading instructions

OCW reloading overview and instructions

www.ocwreloading.com

^This if you're actually doing "OCW". a bunch of 3 round groups with group sizes and velocity spreads isn't giving statistically significant info.

Chalk me up as another that leans closer to the "painless load dev" method. Haven't done OCW in years.

 

[112Savage]

Just a thought as someone with two different 280AI’s
Loading to sticky bolt and backing off 0.5gr will result in reworking that load later. 3-4 loadings later you will have extraction problems due to case web growth. I will admit that my experience is with nosler brass and not Peterson, but pressure hides well in 280AI’s.
My 280AI’s are a 24” Carbon6 (1:8” twist) and a 22” Weatherby with BSF barrel (1:9” twist)

With 160’s in the carbon6 I was able to hit 3000fps with RL23 and RL26
With 160’s in the BSF I could only get 2880 with RL23 (very new barrel <30 shots)

However, due to trashing quite a few nosler brass due to case web and primer pocket growth I’ve decided that sticky bolt lift is way too far in 280AI. It could be the brass but…

 

[Flyjunky]

Just be aware the velocity/pressure your finding right now will with those grain weights will change once those new cases are fire formed to your chamber.

 

[FLHunter87]

What cause the bullet to become more stable?

I have no idea. That's what the guys said. I didn't say that. It's not my advice.

 

[RussDXT]

Ocw is a waste of time and shooting. Got 10% less than max shoot 10 rd groups and see what happens.

 

[pbroski]

Ocw is a waste of time and shooting. Got 10% less than max shoot 10 rd groups and see what happens.

I agree. Shoot many 10 round groups. Watch how each individual shot populates each group, and it will eventually become clear that OCW can't possibly work as Newberry describes it. The Form method is the best method for the beginning reloader, IMO.