I believe, but haven't proved it as fact, my 222 loaded with BLC-2 is being affected by cold temps. As the rounds cold soak the groups open up quite drasticly. I have a little carrying case I can put these loaded rounds into that I can insulate. My question is what can I put into this carrying case to retain or put off heat to keep these loaded rounds warm? There are items that can be put into the freezer then later into an insulated container to help keep things cool. What can I heat up in the microwave then put into my insulated carrying case to keep things warm, like my loaded rounds? It is 10 degrees out there right now and I want to go to the range.
Keeping loaded rounds warm
- Thread starter hedditch
- Start date
Erik Cortina
Team Lapua Brux Borden Captain
Why don't you just increase your powder charge?
TheBlueEyedBear
'The Nut Behind The Trigger'
Here in Montana when hunting in cold weather I always keep my loaded rounds in an inside pocket next to my body to maintain the warmth of the ammo. I don't take it out until ready to shoot. Letting it lie in a cold chamber would be defeating the purpose.
What's the general consensus on shooting groups in cold weather, how much worse should you expect things to be? I'm trying to do some load development in 20 degree weather and wonder if I'm just wasting time and $$. I'm trying to keep the rounds somewhat warm but I think the temperature of the rifle varies so much it's probably all moot. It seems like group sizes are doubled, at least.
swehrman said:
Yes, they do work. Put the warmer in a soft insulated cooler along with your ammo.
Bill
kentuckytroutbum said:
That is a good idea. I was going say to use one of those hot or cold wraps you can freeze or microwave, in a cooler. I try to tune for the condition I'll be shooting though.--Mike
LawrenceHanson said:
You are right on point # 2 , but wrong on point #1.
If you keep your gun and ammo at summer temps, you can find a summer tune. Period. If you let your gun or ammo cool, then yes, you are wasting your time.....All of the things you listed ( temp, air density, baro...ect..) relate to EXTIRIOR balistics...they may change where your group is on paper, but the group size will not change if the gun/ammo combo stays warm.. If he in fact is trying to find a winter load then he should let his ammo and gun sit untill they are cold.
hedditch said:
Temperature affects tune. No if and or buts about it. So what's the remedy? Tune your barrel in the predominant conditions you expect to be shooting in during the winter. If it's 25 degrees most of the time, find the barrel tune for that condition or temperature and make adjustments when needed.
Something I collected along the way, for my Benchrest file, for future reference and refer to when I'm reloading:
***"Temperature? This is the big one! It's actually the only thing you must concern yourself with. The temperature range from being perfectly in tune and being completely out is 20 degrees F.
Yep, if your rifle is perfectly in tune during the first match of the day when temperature is 70 it will be completely out of tune when the temp reaches 90 if you do nothing to compensate.
To keep the rifle in tune throughout the day, reduce the velocity 30 fps for each five degree increase in temp."*** ... Gene Beggs, Benchrest Central http://benchrest.com/forum.php
Lets test this a little further....hypotheticaly.....the topic is fairly interesting, but widely debated. I have also seen this dabated on BRCentral.
Lets shoot some groups. But we are going to have a special setup. Our entire shooting system is in a 15' x 15' enclosed building. Insulated, with both heat and AC. This is where we keep our gun stored. This is where we reload and store our ammo and components. This is where the bench is...we shoot out a window. The interior temp is kept precisely 70 degrees F. 24-7-365. (Except for the AC, I know people who have this setup. And most of us have read the "Fist Of God" articals in PS.) In honor of this website we will be shooting 105 Berger VLD's in a 6BR with RL 15 @ 2850 fps.
We are going to shoot groups at 100 and 600 yards in 0 degree and 100 degree temps (outside temps).
Now, there is no argument the the POI will shift with this huge temp swing, and the termanal velocity will change also. Cold air is denser than warm air. There is a 27 FPS diff of impact speed at 100 and 129 FPS diff at 600 (Sierra I-6). But, our muzzle velocity is 2850...all day long. Every day.
So, I put forth the question.......the outside temps are wildly different, but we fooled our shooting system into thinking that it has remained a constant 70 degrees by artificialy controling the gun and ammo's temp......will the OUTSIDE temps (exterior balistics) affect group SHAPE AND SIZE? Will it affect the longer ranges more than the shorter (as a percentage)?
Yes or no.
And if no, why.
I know that some of the best shooters in the world visit here often. Lets hear what they have to say.
Lets shoot some groups. But we are going to have a special setup. Our entire shooting system is in a 15' x 15' enclosed building. Insulated, with both heat and AC. This is where we keep our gun stored. This is where we reload and store our ammo and components. This is where the bench is...we shoot out a window. The interior temp is kept precisely 70 degrees F. 24-7-365. (Except for the AC, I know people who have this setup. And most of us have read the "Fist Of God" articals in PS.) In honor of this website we will be shooting 105 Berger VLD's in a 6BR with RL 15 @ 2850 fps.
We are going to shoot groups at 100 and 600 yards in 0 degree and 100 degree temps (outside temps).
Now, there is no argument the the POI will shift with this huge temp swing, and the termanal velocity will change also. Cold air is denser than warm air. There is a 27 FPS diff of impact speed at 100 and 129 FPS diff at 600 (Sierra I-6). But, our muzzle velocity is 2850...all day long. Every day.
So, I put forth the question.......the outside temps are wildly different, but we fooled our shooting system into thinking that it has remained a constant 70 degrees by artificialy controling the gun and ammo's temp......will the OUTSIDE temps (exterior balistics) affect group SHAPE AND SIZE? Will it affect the longer ranges more than the shorter (as a percentage)?
Yes or no.
And if no, why.
I know that some of the best shooters in the world visit here often. Lets hear what they have to say.
Erik Cortina
Team Lapua Brux Borden Captain
As long as you control the elements to make the rifle shoot at the same speed, in this case 2850, therefore the barrel harmonics will be the same, therefore accuracy will also be the same. The outside temperatures will simply make it strike lower or higher on the target depending on outside conditions.
There is some danger in tuning at cold temps and then shooting in hot. You may find the load way too HOT when things warm up. Happened to a friend of mine durring a Pdog shoot - the loads he developed on a 70deg day had to beaten out of the gun on a 90deg day. I am not talking about a round that sat in the gun and baked in a hot chamber either - this guy shoots maybe 100 dogs a day and his gun never gets hot. This ruined his week in SD - he was one gun down since he had no way to reload.
shootsanything said:
This applies to ammo only.
How can this be?
Lets look a a typical 1000 yard HG relay...with my gun......booming 300 magnum on a 17 lb platform. Not most peoples choice for a HG platform with the thin BBL. Most guys shoot between 5 and 10 sighters...more if the conditions are bad. I shoot LOTS!!!! Unless you are short of ammo, usually never less than 5.
Most of the sighters are taken in the last min. I shoot a shot at 1 min, 45sec, 30, 15, and 1 second. I accomplish two things...I (hopefully) figured out the conditions, and two, I built up heat in my BBL. This is a good thing. I have had conversations with two BBL makers, a few TOP BR smiths, and many world class shooters.....Heat is a good thing in a BBL. Now, I am not talking about red hot, and excessive heat kills BBLS. But, I switched from ejecting my fired rounds and waiting with my bolt open to help cool the bbl , to leaving the bolt closed on the fired case untill I am ready to send another sighter down range.
Now ten seconds after the sighter period I am going to send ten belted magnum .30 cal rounds down range in 30 to 45 seconds. Now.....I don't know how hot the bbl is when i started to shoot, how hot it is after the sighter period, (but it is VERY warm).....but it is FRIGGIN SMOKIN when I am done with my 10 shot string. If you try and pick up the gun by the tube, you will burn your hand. But...I started with a GOOD bbl...properly stress relieved. The exterior temp of my bbl has increased what...50 degrees, 100 degrees, 150???? How about the internal temp.....god only knows. But from the first record shot to the 10th...nothing has changed on target. My POI has not changed...I have shot enought 4, 5, and 6 inch ten shot groups to know that. ANd my 10th shot left the tube at the same speed as the first. No ejection problems. No "heat" problems. No going out of tune problems. The only time I ever notice my loads getting "warm" and the little telltale hitch at the top of the bolt throw is if I let my ammo sit out on a hot day. Then it is trouble right from the first sighter shot.
Lets say I have a screw up....I don't pull the trigger on the tenth and final round...for what ever reason....upset the gun, condition change,,,whatever. The round cooks in my chamber for 30 seconds. I can not pull the round, I WILL have a stuck bullet and a chamber full of powder. Now, what do you think will happen to that round when fired? It has happend to me twice (not the tenth both time). The first target I had a flyer high. Was it that shot? I don't know. The second time I aimed at the bottom of the blue and had a nice round group.
It is not the temp of the gun that messes things up. It is the temp of the ammo. Leave the ammo out on a hot day and things will go to hell in a hurry...from simply going out of tune to stuck bolts. Cold ammo will not stick you bolt, but it will raise hell with your tune. If you can keep your ammo at or near the temp you "tuned" ...whatever...60, 70, whatever... degrees... It doesn't matter if it's 100 degrees or zero outside...your tune will not change.
Exterior balistics don't change your tune or your groups size / shape. Your BBL should shoot the same . Hot or cold. Your ammo will not. Keep your ammo in a cooler in the summer and add heat in the winter, and you will be good to go.
I found the tune for my new HG in feb 2010 ....in ND.....20F. I kept my ammo warm, and kept the heat in my gun by shooting......and this EXACT load placed me forth in HG at the IBS nats. This load went out of tune once....in Iowa...when I left the ammo boxes out in the sun. Later on that dayI stuck them in a cooler of ice for a little bit and the tune came back. The load I found in my LG was found in March 2008...in ND....and it placed me third in the IBS SOY points that year, and placed me fifth in two gun overall at the IBS nats the next year.
4xforfun,
How are you keeping your ammo warm? I have seen three suggestions: keeping the ammo close to your body, hand warmers, and hot water bottles. Your method? Sounds like you have to keep alot of ammo warm at the same time. My last time out to the range I had over 100 rds of various calibers.
How are you keeping your ammo warm? I have seen three suggestions: keeping the ammo close to your body, hand warmers, and hot water bottles. Your method? Sounds like you have to keep alot of ammo warm at the same time. My last time out to the range I had over 100 rds of various calibers.
4xforfun
I think there will STILL be affects in grouping, but couldn't prove it.
-If I assume your barrel is sticking out a window, it's bore is filled with air that varies in density with outside conditions. Bullets have to push this air out with a piston action, and I think this will affect MV and tune(barrel time).
-With the same assumption, stability is affected by outside conditions, both gyroscopic and dynamic. From 0 to 100deg, and depending on your shooting system, this 'could' be significant(it would be for some of my systems).
-BC changes with outside conditions and this directly affects wind drift,
and possibly your ability to compensate with the same results.
-There will be mirage at higher temps that isn't there for colder shooting.
-Your heart beat is faster from shoveling a path to your man-hut at zero degrees!
I think there will STILL be affects in grouping, but couldn't prove it.
-If I assume your barrel is sticking out a window, it's bore is filled with air that varies in density with outside conditions. Bullets have to push this air out with a piston action, and I think this will affect MV and tune(barrel time).
-With the same assumption, stability is affected by outside conditions, both gyroscopic and dynamic. From 0 to 100deg, and depending on your shooting system, this 'could' be significant(it would be for some of my systems).
-BC changes with outside conditions and this directly affects wind drift,
and possibly your ability to compensate with the same results.
-There will be mirage at higher temps that isn't there for colder shooting.
-Your heart beat is faster from shoveling a path to your man-hut at zero degrees!
mikecr said:
Mike...first.....mirage is not Exterior balistics..it is a condition.
Wind is not exterior balistics...it is a condition.
Heart beat is not extirior balistics..it is a shooter induced factor, which is not in question here. No one is arguing that it is more difficult to shoot when it is cold out....just saying that it is not INPOSSABLE to shoot in cold weather...especialy free recoil. And don't forget...we LIVE in our man cave!! I forgot to mention that we also have a fridge full of beer, a stove, cable tv, and a "no women allowed" poster on the door!! There will be no shoveling. ;D
Who said the bbl is sticking out the window....not me....you are changing the experiment. And I can tell you that the air temp inside the bbl after a few sighter shots is friggin hot..it makes no differance what the outside temp is.
So, my question to you is this...does EXTERIOR BALISITCS affect group size and shape?
Upgrades & Donations
This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.