I'm working up several loads (variety of bullet weights) in an '06 with a light sporter barrel (not a std. sporter but not a featherweight either). I find that even waiting 2 min. in between shots that 6 shots is about maximum before the barrel is difficult to keep "relatively" cool unless....left alone for about 20 or so minutes.

What are your thoughts/methods for load testing regarding accuracy and shot frequency? Ultimately, when I find my best 168 gr. load, I would like to participate in my club's monthly 600 yd. shoot. The requirement is shooting 20 rounds in 20 minutes. There is no way I could shoot 20 rounds in 20 minutes without a very hot barrel.

My personal criteria is that if the barrel is not hot enough to boil water/sizzle it is not hot enough to damage the metal. 212 degrees F (100 C) should not hurt modern barrel metals. As far as shooting, if I can hold my hand on it with discomfort but no pain, I allow one more shot. Not scientific by any means, but so far, so good!

For accuracy, keeping the barrel heat as close as possible to the previous shot should give the most consistent results, whether that is complete cooling or just getting back to comfortably warm.... Others I am sure have a favorite method too, this works for me.

I've done a lot of "anal" soul-searching on this topic. To my way of thinking, it's what your rifle does with the FIRST SHOT that counts, that is, if your rifle shoots that first shot consistently in the same place, you're in pretty good shape. I like 3 shot groups then let the barrel cool all the way down to ambient temp ( or almost).
Or, I find that if a fire a 3 shot group and let the barrel cool after each shot, there is slightly better accuracy that way. I shoot a lot of Weatherbys and/or magnum rifles and I find that after 3 shots, accuracy declines. Down here in Florida where it gets pretty hot i the summer, I have to wait around 20 minues per 3 shot group in order to get full cooldown. jorge

If your going to use a scope on that 06 and fire 20 shots in less than 20 minutes you have better make up an elastic tape to hold over the barrel. After about four shots the mirage from the barrel will become a problem. This tape can be found in sewing stores or at target shooting suppliers.



Since that's the course of fire you should shoot the rifle the same way.



For testing of hunting rifles I take a different approach. I shoot two shots, record the results and pick up another rifle and do the same. It takes about five rifles to make a perfect round robin. As Jorge says it's where the first shot hits that really counts.

To keep my barrels from overheating, I place a damp rag over them. I fire a 3 shot group then place the rag (folded over on itself a couple of times) over the length of the barrel. In 5 to 10 minutes the barrel will have cooled all the way down to the ambient temperature. While this one is cooling, I shoot something else. By doing this, I loose no shooting time due to an overheated barrel. I have actually shot my rifles with the damp rag over the barrel and have noticed no effect on accuracy and keeping the rag on them this way cools them even faster.

Couple more comments:

Barrel temperature has a stronger effect on pressure and muzzle velocity than the temperature of the cartridges does. If your POI changes as a result of temperature, this could be an issue.

According to one competent author, the temperature difference between the inside and outside of the receiver is an issue. His theory, and it sounds right, is that you can eliminate a lot of thermal "fliers" by using a SpiraLock thread on the barrel, which distributes the thread load more evenly. Apparently, it is hard to make a really rigid threaded joint... possibly the reason Savage went to the hotly debated barrel nut.

It's not very expensive to simply tape a cheap thermocouple to the barrel, just in front of the receiver, and to monitor changes in POI as a function of temperature. I do this all the time in load development.

You'll probably do better if you shoot a couple of "fouling shots" to start bringing your gun up to temperature before the actual contest starts. You temperature may be high, but it will be more consistent.

Same author that likes SpiraLock threads also says that adding a .3 pound muzzle weight will reduce barrel vibrations considerably. That's something that could be easily added for target shooting, and removed for hunting.

Hope this helps. Good luck.

To all - your input has been very educational; thank you.

You'll probably see the better shooters shoot their two sighters and 20 record shots in about 10 minutes, if pit service is good. That's to avoid having to shoot over a wide range of wind conditions - find a condition and let 'em rip. Remember, each shot will be scored and spotted, so if they start to climb, simply adjust the sights accordingly. A decent barrel that's free floated shouldn't have a problem. You'd probably have a hard time telling which elevation changes are due to a hot barrel versus the ones caused by mirage, load variation, and perish the thought, shooter error.

Timed shooting events are tough events since you must deliver your shots in a certain amount of specified time. I have always maintained if your barrel is more han luke warm toyour touch your shooting to fast. I am a recreational group target shooter and do have to deal with time contraints. You must contend with the sporter weight barrel and it is certain your barrel will become very hot shooting 20 rounds in 20 miuntes. I would first rebarrel to a heavy barrel configuration if weigth limits can be met by doing so. I care not for timed shooting events unless I can use a heavy barrel to absorb more heat and limit group swell due to excessive barrel heat up.

You would be better off shooting the 308 as it burns less powder per round than the 30-06 and is inherantly more accurate. The 308 shooting the Nosler 155 grain HPBT J-4 bullet should perform very well at 600 yards. It is always best to compete with the proper cartidge for the event you intend shooting. Kinda like shooting benchrest with a 220 swift when you know the 6ppc is the proper cartidge you should use to be in contention.

Heck, I just put the snow or ice directly on the barrel. PRESTO! One thing I HAVE noticed is that it does take a minute or two for the cold to "even out" throughout the barrel and get to the action.

Most competitive shooters do not shoot lighweight barrels. There is a big heat-sink in a bull barrel. JMO, Dutch.