My Summary of the “groups to small” “painless load dev” and Shoot2Hunt

[philcox]

Based on the Hornady podcast about group sizes, @Formidilosus “painless load dev” post, and the @Shoot2Hunt podcast. I have tried to summarize of all of that information. Correction of my understanding, were I got it wrong, is appreciated.

Process:

1. Define what you realistically want (need?) out of a rifle and load.
2. Pick quality components that should likely give you what you are looking for
3. Load it up. Try to be consistent, but don’t go OCD on minute details (charge weight and seating depth - small deviations are not the issue)
4. Shoot a group of 10 and see if you get the minimum (e.g., fps) or max (e.g., MOA) defined in step 1. If so, go with that and shoot. If not …
5. Make sure everything is tight and proper clearances. Drop 1g and repeat 3&4
6. If still nothing, find a different bullet and repeat 2-5
7. If still nothing works, either get a new barrel or maybe try a recommended factory load that the barrel manufacturer recommends

Note on step 4: the Hornady guy said that you should do this like you Hunt. o if you shoot three shots out of your hunting rifle, then don’t shoot it for a while, the 10 shots should be in groups of three, and either let it rest, or shoot it another day. Just make sure that you’re using the same point of aim, so the groups can be measured together. There is another thread that talks about hot and cold bore shooting, in which it appears that it doesn’t matter, and you could shoot all 10 rounds in the same sitting (correct @Formidilosus ?), and essentially have the same statistical group that you would if you went day after day, or let the barrel cool.

There is an assumption in the latter discussion, that the components you have are quality rise. I think the Hornady podcast, would be applicable, whether you had quality components or not.

Update: Episode 37 from Shoot2Hunt with the Hornady guys was valuable too.

 

[Formidilosus]

Note on step 4: the Hornady guy said that you should do this like you Hunt. o if you shoot three shots out of your hunting rifle, then don’t shoot it for a while, the 10 shots should be in groups of three, and either let it rest, or shoot it another day. Just make sure that you’re using the same point of aim, so the groups can be measured together. There is another thread that talks about hot and cold bore shooting, in which it appears that it doesn’t matter, and you could shoot all 10 rounds in the same sitting (correct @Formidilosus ?), and essentially have the same statistical group that you would if you went day after day, or let the barrel cool.

Overall, that is a good summery. For the above, that is correct. Other than barrel mirage, if the barrel is properly stress relieved and the rifle is assembled correctly there is no difference in cold, warm, or hot bore shots or groups. If the barrel isn’t properly stress relieved, or if the rifle isn’t assembled correctly that is a legit problem and you want to know that- it needs to be addressed.

A rifle that doesn’t shoot into the same cone as it warms up as it does when it is “cold” (and why is it always the first three shots are ok, but magically it’s the fourth that causes problems?) needs to be fixed.

 

[Mountainrancher]

Overall, that is a good summery. For the above, that is correct. Other than barrel mirage, if the barrel is properly stress relieved and the rifle is assembled correctly there is no difference in cold, warm, or hot bore shots or groups. If the barrel isn’t properly stress relieved, or if the rifle isn’t assembled correctly that is a legit problem and you want to know that- it needs to be addressed.

A rifle that doesn’t shoot into the same cone as it warms up as it does when it is “cold” (and why is it always the first three shots are ok, but magically it’s the fourth that causes problems?) needs to be fixed.

As far as shooting 3 then letting it cool until you get to a 10 or 15 round group one reason I’ve heard for doing this is that it will help with barrel life specifically in magnums and overbore cartridges. No clue if it’s true or not or even necessary as most people (myself included) really don’t need to worry about shooting out a barrel. Is there any validity to this in your experience form?

 

[Formidilosus]

As far as shooting 3 then letting it cool until you get to a 10 or 15 round group one reason I’ve heard for doing this is that it will help with barrel life specifically in magnums and overbore cartridges. No clue if it’s true or not or even necessary as most people (myself included) really don’t need to worry about shooting out a barrel. Is there any validity to this in your experience form?

Yes. The hotter the throat gets, the more it wears. However, it is greatly overblown. A couple 20-30 round groups over a barrels lifespan is immaterial. Doing 20-30 round groups and getting the barrel sizzling hot every time you shoot it? Yes, that will cause accelerated wear.

Unless you are replacing worn out barrels each year on the same rifles, barrel wear is not a thing that should concern someone.

 

[sierracharlie338]

Overall, that is a good summery. For the above, that is correct. Other than barrel mirage, if the barrel is properly stress relieved and the rifle is assembled correctly there is no difference in cold, warm, or hot bore shots or groups. If the barrel isn’t properly stress relieved, or if the rifle isn’t assembled correctly that is a legit problem and you want to know that- it needs to be addressed.

A rifle that doesn’t shoot into the same cone as it warms up as it does when it is “cold” (and why is it always the first three shots are ok, but magically it’s the fourth that causes problems?) needs to be fixed.

In your experience do “most” smiths or barrel makers stress relieve barrels or is it something that should be asked for? At what point in the barrel purchase/rifle build should this be done?

 

[rifletuner]

In your experience do “most” smiths or barrel makers stress relieve barrels or is it something that should be asked for? At what point in the barrel purchase/rifle build should this be done?

Since you are asking about a smithd barrel, my answer is focussed on custom barrels rather than factory barrels.

Gun smiths dont stress relieve barrels. It is done as part of the barrel making process. Any top tear barrel (ie Bartlein, Kreiger - just names I am using as I am personally familiar with them) will be stress relieved. Stress relief is not something you should have to ask for.

 

[sierracharlie338]

Since you are asking about a smithd barrel, my answer is focussed on custom barrels rather than factory barrels.

Gun smiths dont stress relieve barrels. It is done as part of the barrel making process. Any top tear barrel (ie Bartlein, Kreiger - just names I am using as I am personally familiar with them) will be stress relieved. Stress relief is not something you should have to ask for.

That was my understanding prior to reading Forms post but wanted to make sure I didn’t have an incorrect understanding.

 

[Marbles]

Nice summary.

Another consideration for not banging off groups rapidly is shooter fatigue. Obviously this is individual, will change with increased practice, and is less significant for lighter recoiling cartridge/gun combinations.

If the gun moves with heat, I say scrap it. My rifles can realistically be shot in conditions from sub -40 to 120 F, if three shots heat it enough to move POI, then you can bet POI will differ from a "cold bore" over that 160 degree temp range.

Ideally, stress relieving happens after the last machining process. However, done properly, with sharp cutters, even fluting should not introduce stress. Done poorly, it can. (My understanding, I'm not a machinist, nor an engineer)

Because I think it is cool.
Cold hammer forged barrels do not need to be stress relieved. There is no cutting or machining (other than threading the barrel tenon and muzzle) and one process forms the chamber, rifling, contour, and fluting. The limit to cold hammer forging is tooling, the mandrel sets the chamber and rifling specs, and customization is not really an option as it would require the creation of a new mandrel, making it cost prohibitive. Cold hammer forging work hardens the entire barrel, and the work hardened throat is more resistant to erosion than a cut throat (this is probably why Form's 223 is still going after 20K rounds).

 

[Formidilosus]

In your experience do “most” smiths or barrel makers stress relieve barrels or is it something that should be asked for? At what point in the barrel purchase/rifle build should this be done?

The barrel makers do it as stated in the other posts. I haven’t seen a barrel from a legit barrel manufacturer that wasn’t stress relieved properly. At least in the last 20 years. Further, all the European and Scandinavian barrel and rifle makers also stress relive their barrels, or hammer forge them and don’t have to worry about it. Again, at least in the last 20-30 years.

Barrels with stress in them is really a domestic US, garbage manufacturing issue. Historically Remington, Winchester, Ruger, Savage, Kimber, etc. Savages, Rugers, and Kimbers still show it from time to time; I haven’t seen a new Remingtons to say there. Winchester seems to have got it under control. The “semi custom” brands have issues at times as well- Bergara, Christianson, etc.

 

[Reburn]

The barrel makers do it as stated in the other posts. I haven’t seen a barrel from a legit barrel manufacturer that wasn’t stress relieved properly. At least in the last 20 years. Further, all the European and Scandinavian barrel and rifle makers also stress relive their barrels, or hammer forge them and don’t have to worry about it. Again, at least in the last 20-30 years.

Barrels with stress in them is really a domestic US, garbage manufacturing issue. Historically Remington, Winchester, Ruger, Savage, Kimber, etc. Savages, Rugers, and Kimbers still show it from time to time; I haven’t seen a new Remingtons to say there. Winchester seems to have got it under control. The “semi custom” brands have issues at times as well- Bergara, Christianson, etc.

Dont forget weatherby.....

 

[Formidilosus]

Dont forget weatherby.....

Ha. No doubt.

 

[sierracharlie338]

The barrel makers do it as stated in the other posts. I haven’t seen a barrel from a legit barrel manufacturer that wasn’t stress relieved properly. At least in the last 20 years. Further, all the European and Scandinavian barrel and rifle makers also stress relive their barrels, or hammer forge them and don’t have to worry about it. Again, at least in the last 20-30 years.

Barrels with stress in them is really a domestic US, garbage manufacturing issue. Historically Remington, Winchester, Ruger, Savage, Kimber, etc. Savages, Rugers, and Kimbers still show it from time to time; I haven’t seen a new Remingtons to say there. Winchester seems to have got it under control. The “semi custom” brands have issues at times as well- Bergara, Christianson, etc.

Awesome that’s what I was under the assumption you were referring to but wanted to clarify.

 

[Harvey_NW]

Note on step 4: the Hornady guy said that you should do this like you Hunt. o if you shoot three shots out of your hunting rifle, then don’t shoot it for a while, the 10 shots should be in groups of three, and either let it rest, or shoot it another day.

Depending on the day after 5 in a row mirage usually starts to get bad, so I like to take at least 2 guns at a time and shoot slow 5 shot strings. Pull the bolt, set it in the breeze, grab the other one. Shooter fatigue is important, as mentioned. I'm working on an ultralight custom 300PRC right now that shook me pretty good last outing, made me realize how much I appreciate the lesser recoiling rifles.

 

[philcox]

Update: I am sending barrel back to CarbonSix, they are going to check it out and see if they can see anything amiss. I am 200 rounds down the barrel and could not get a 10 shot group consistently at 1.5 MOA. Actually, I did get 1 10 shot group at 1.17 MOA/0.38 Mean Radius (168 LRX 66.5 H4831SC), but the bolt lift was hard on all the shots. I then dropped the charge to 65.5, and first 5 shots 1.13 MOA/0.39 MR, but after 10 1.64 MOA/0.69 MR. For a barrel that has a .5 MOA guarantee, I won't be satisfied unless I can get a consistent 1.5 MOA gun. Does not seem to be an unreasonable expectation.

I'll come back to this an update once I get either a new barrel or this one back confirmed that it is "good".

 

[Holycross07]

Overall, that is a good summery. For the above, that is correct. Other than barrel mirage, if the barrel is properly stress relieved and the rifle is assembled correctly there is no difference in cold, warm, or hot bore shots or groups. If the barrel isn’t properly stress relieved, or if the rifle isn’t assembled correctly that is a legit problem and you want to know that- it needs to be addressed.

A rifle that doesn’t shoot into the same cone as it warms up as it does when it is “cold” (and why is it always the first three shots are ok, but magically it’s the fourth that causes problems?) needs to be fixed.

How does a guy figure out if it is lack of stress relief on the barrel on poor rifle assembly? There is a lot of good info here and it is a great place to learn.

 

[Formidilosus]

How does a guy figure out if it is lack of stress relief on the barrel on poor rifle assembly? There is a lot of good info here and it is a great place to learn.

Process of elimination. There are best practices of how to assemble a rifle, check free float, mount a scope, etc. Shoot statistically relevant shot groups sizes/ 1 plus round per group. Once those are done and checked, swap scopes. Once that has been done and the issues continue, the rifle needs to be looked at.

 

[Holycross07]

Thanks for the info, I appreciate it!

 

[philcox]

UPDATE: I have my new barrel from CarbonSix. I have deviated a bit from what I understand is the "ideal" path:

1. I want the 168 LRX as the bullet. I choose Ramshot Magnum as the powder. I found Hogdon load data for that combo, with a Max Load of 70.7. For this bullet, I am looking at 2900 fps as the goal for distance I want.
2. I loaded 70.7 and shot it. No pressure, but velocity was WAY too low (2700 ish).
3. I then decided to deviate from "ideal" and walk a ladder to see if I could get to the velocity I wanted. I loaded 71.2, 71.7, 72.2 and shot those. No pressure and 72.2 was 2832 (getting there, but not what I wanted)
4. I then wanted to get a "base accuracy" and shot a box of 180 ELDM Factory. This essentially gave me a baseline of 1.75 MOA (hunter+rifle+load) for 2 10 shot groups. Base is now set for any use outside of California
5. I then went back to "ladder" and 72.7, 73.2, 73.7, 74.2 ... No Pressure (no bolt lift, no ejector marks, no flat primers). 74.2 got to 2918, so now I have a combo that meets my minimuns. NOTE: The fact that I am almost 4g over the book max of Hogden does have me questioning things. Not sure if I am pushing it too much, but because of seeming lack of pressure, I am going to try it. @Formidilosus is this a dumb thing?
6. I have now loaded 10 168 LRX @ 74.2g Ramshot Magnum (ADG, CCI 250) @ 3.20. I will shoot a group of 10 (actually 2 of 5 same POA) and see if as good or better than the 1.75MOA with the 180 ELDM. If I get that, I will call it "good enough" and load that and start practicing. If not, I'll drop 1g and try another 10.
7. I am also going to shoot a box of 175 ELDX (4 groups of 5, same POA) and see if that is any better than the 180 ELDM. This again is more of determining what "factory" load I can use out of Cali if needed and what the limitations will be.

As a reminder: Tikka w/ 20" C6 Barrel.

 

[Formidilosus]

1. I then went back to "ladder" and 72.7, 73.2, 73.7, 74.2 ... No Pressure (no bolt lift, no ejector marks, no flat primers). 74.2 got to 2918, so now I have a combo that meets my minimuns. NOTE: The fact that I am almost 4g over the book max of Hogden does have me questioning things. Not sure if I am pushing it too much, but because of seeming lack of pressure, I am going to try it. @Formidilosus is this a dumb thing?

In general, velocity is pressure. It wouldn’t concern me terribly, but I would keep on eye on it because as the barrel settles and if you don’t clean (I wouldn’t), velocity and pressure probably will start creeping up. Later you may want to drop charge a bit.

 

[philcox]

In general, velocity is pressure. It wouldn’t concern me terribly, but I would keep on eye on it because as the barrel settles and if you don’t clean (I wouldn’t), velocity and pressure probably will start creeping up. Later you may want to drop charge a bit.

Will keep that in mind. Thx.