Zeroing, grouping, and barrel heat

[philcox]

Pretty new to this whole process (haven’t done any serious rifle hunting since a kid). I have a New Savage Storm 110 in a 270 win. For all practical purposes, when I am Zeroing (Leupold VX-3i 4.5-14x40) I am using one cartridge at a time, but I’m curious if I need to wait a specific amount of time between shots, so not as to have barrel heat potentially affect the zero and or groupings?

 

[JBradley500]

Today I zeroed my 308 again. The groups are terrible if I shoot too many shots in a row without waiting. It starts to throws them all over the paper after 6 or 7 shots. If I let it sit 5 or 6 minutes between shots (bolt open, barrel pointed in the air) the barrel will then feel close to ambient temperature and will group well. The barrel is a pretty light contour and it will work for a deer gun but not target competition.

On the other hand, other guns I have will plug them right in there tight and I don't need to think about heat or anything else.

I guess my point is that from my experience it just depends on your gun. You'll have to figure out what works best. I tried to find any "rules" about this today when waiting between grouping some shots and I couldn't find any.

 

[swampthing]

Depends on your caliber. The fast shootin rounds really heat the barrel. A guy does need to check his zero with an absolute cold barrel. On my fast weatherbys like the 257 and the 6.5 i give 5 minutes between shots and 15 minutes between groups. On my 243 I can shot a group in 5 minutes and only wait 5 minutes before the next group. And like I mentioned, always re check your zero with a cold barrel after.

 

[AZ_Hunter_2000]

I just zeroed a Savage 110 Storm this past weekend. It was in the upper 90s.

Bring along other firearms and shoot them periodically to let your 270 cool down.

During the zeroing process, I'll give it 2-5 minutes between shots. I do set a timer on my phone. Depending on the barrel heat as well as the air temperature, then I'll also throw a damp wash cloth on the barrel. During the process feel free to shoot your other firearms.

When shooting groups, I'll do a similar time break between shots as well as using a damp clothe when needed. Depending on caliber, I may pivot to shooting a rimfire for a bit to get "recoil" off of my mind.

On future range sessions, I will shoot that newly zeroed rifle. I'll confirm the cold bore zero. I will do 3-4 quick, accurate shots (the number is based upon the number of rounds I can fit into the magazine) to see the effects of the barrel heating up. After a few sessions I'll have a better idea of what is likely to happen if things go south and I need to take more than 2 quick shots on an animal at various distances.

 

[Rich M]

Shoot 2 or 3 shots them adjust your scope. Center the group on the bullseye.

Shoot for x at 25 yards then 100 then wherever you want.

Zeroing for 100 yds should be quick and easy.

 

[philcox]

Based on "real world" hunting situation, I need to plan for 2-3 shots in a short (< a few min apart) shots. Since I need to be confident of the "grouping" in that situation, I will shoot those and see how it reacts. I am currently shooting the Barnes 129gr LRX, and will try the 130gr TTSX to see if any better groupings with that. I also am planning a "worst case" of 700yds (using the Vortex LRBC for the LRX, and a min FPS of 1800, that is about the limit of that bullet in my calibur. For the TTSX it is about 550yds).

We'll see how it goes. Thanks for all the input.

 

[slowelk]

Based on "real world" hunting situation, I need to plan for 2-3 shots in a short (< a few min apart) shots. Since I need to be confident of the "grouping" in that situation, I will shoot those and see how it reacts. I am currently shooting the Barnes 129gr LRX, and will try the 130gr TTSX to see if any better groupings with that. I also am planning a "worst case" of 700yds (using the Vortex LRBC for the LRX, and a min FPS of 1800, that is about the limit of that bullet in my calibur. For the TTSX it is about 550yds).

We'll see how it goes. Thanks for all the input.

A lot of folks can attest to the fact that you need a little cushion on the stated expansion velocities of copper monos. To be really safe you should add 200fps to the stated expansion specs. As you probably already know, the LRX has a lower expansion velocity requirement, but I'd still err on the side of caution.

 

[philcox]

A lot of folks can attest to the fact that you need a little cushion on the stated expansion velocities of copper monos. To be really safe you should add 200fps to the stated expansion specs. As you probably already know, the LRX has a lower expansion velocity requirement, but I'd still air on the side of caution.

Understood. As I get a bit more time behind this scope, I'll know more. I definitely will err on the side of caution, and in all reality, with my scope setup, am more likely to be in the 400-500 max range.

 

[Doc Holliday]

I wait 2 minutes between shots

 

[Motown]

Everyone is going to give a different answer for this. Personally if I am shooting a rifle with a sporter weight barrel and it is warmer outside I will shoot 3 shots giving around 2-3 mins between shots. After the 3 shot group is finished I let them sit for 10-15 mins before repeating another 3 shot group. If you bring another rifle or two with you then you will not even notice the wait time between groups.