Fouled vs clean bore for hunting

playin' hookey

New member
Given that the rifle is zeroed with a fouled bore, how important is it to fire a shot before each hunt to foul the bore? What do you do?
 
I sight in with hunting ammo the week before season opener and hunt on a dirty bore.

P.S. always check the zero one shot on a cold barrel, heat changes poi.
 
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If it's zeroed to a fouled bore, as in shot until you get consistent groupings or desired POI... you're good to go.
The only common thing that might affect POA/POI would be a temperature substantially different than the one you zeroed the gun in... or when you zeroed the gun, the barrel was really hot by the time you got it to hit desired POI.

C
 
My hunting rifles only get their bores cleaned once a year. Clean, then foul, resight, then leave the bore alone until next year.
 
With my main rifle, A H&R .308 Handi-Rifle, I zero, clean, dry swab, shoot 3 shots with a clean cold dry bore to recheck zero. If it's good I clean dry swab the bore and hunt clean. I'm consistently under 2" at 200 yards and I figure all I need is 4" at 100 yards so I don't lose much sleep over a 1/2" or 3/4" drift from clean vs dirty, I just like clean.
 
I have a considerable advantage since I have my own ranges(25,100,150,and 330 yards) and can shoot when/how I choose. I select the rifle(s) I'll be hunting with and check the zero from storage. I clean them conservatively and shoot the next day or two and recheck cold/clean bore zero. Do that again a couple of times and I know where my first, second, and third shots will be. Sometimes, I just fire one shot per day and clean. Next time I might shot 2 or 3 or maybe shoot a 5 shot at 300 meters.
The way our seasons/licensing works here, it's seldom that I just shoot once per day during deer season. With multiple doe tags, I might shoot 2 or 3 deer during one day's hunt and only the first shot would be clean bore.
 
I clean after hunting season then fire a couple before next season's first hunt to chk zero and foul bore. I don't like storing them dirty.
 
I give the bore a good cleaning at least twice per year. After hunting season all my guns are broken down and given a thorough cleaning, especially the bores. During the winter, spring and summer I shoot a lot at the range. I'll clean gunk out of the action and wipe down the exterior of the gun, but the bore doesn't get cleaned until accuracy starts to deteriorate, or if it gets wet.

Most guns are more accurate after 10-15 rounds have been shot through a clean barrel and accuracy does not suffer until 200-300 rounds have been fired. Just depands on the individual gun. Sometime in the next month or so they will get another thorough cleaning, then back to the range for a few more practice sessions to make sure I get 10-15 rounds through each rifle before hunting season starts in mid October. Unless I have to hunt in the rain, they don't get cleaned again until January.
 
I clean it after sighting in and then before the season fire two fouling shots. It's dead on. If I don't the first shot out of a clean barrel is a flyer. Not bad but maybe an inch off at 100.
 
Typically my "fouling" shot is about an inch rightat 100 yards. It doesn't seem like much, but it is enough that I prefer to hunt with a "dirty" bore.

After checking my zero at 200 yards, I will clean, then fire another 5 shot group and be good to go.
 
It takes 4-5 rounds to foul the bore of my match rifles in .223 and .308. At a 600 yard match, my AR-15 will shoot 5 minutes low with a clean barrel. That's 30" low at 600 yards. I used to stop at the 100 yard range, pop off some rounds then go to the 600 yard firing line for the match.

You can always tell the newbies at a 600 yard match. They show up with a clean bore and get ready for prone firing. When the match begins, they furiously dial in "UP" on their sights. After 5 rounds, the barrel settles in and now they're furiously dialing "down" into their sights as now they're shooting over the target.

My answer.....Never go out with a clean bore.

Flash
 
I run a few wet patches of Ed's Red down the bore after sighting in then dry patch it just before the hunt. I've not seen any difference in point of aim with any of the rifles I hunt with. Here in the North Wet, the film left behind from the Ed's Red would be worth it alone for the rust protection.

I also know that some rifles tend to shoot better with a little fouling in the bore. So like many things it depends.

Tony
 
Ditto Edward429 above. It seems like every rifle I ever had shoots the first shot out of a clean bore an inch or more higher than the rest of the first group. When getting ready for a hunt, I shoot 3 shots far enough apart to NOT heat up the barrel, then when it is fully cold, shoot a 3-shot group for zero. Then clean only after the hunt.
 
ROGER4314 states:
It takes 4-5 rounds to foul the bore of my match rifles in .223 and .308. At a 600 yard match, my AR-15 will shoot 5 minutes low with a clean barrel. That's 30" low at 600 yards. I used to stop at the 100 yard range, pop off some rounds then go to the 600 yard firing line for the match.

You can always tell the newbies at a 600 yard match. They show up with a clean bore and get ready for prone firing. When the match begins, they furiously dial in "UP" on their sights. After 5 rounds, the barrel settles in and now they're furiously dialing "down" into their sights as now they're shooting over the target.
All of this is quite contrary to what I've observed over 3 decades of high power rifle competition.

Having shot Remington 40X and Winchester 70 factory match rifles at both 600 and 1000 yards, both types did require a couple of shots through their bores for best accuracy to come about; never more than 3. And yes, they both changed point of impact as their barrels heated up but no more than 1.5 MOA. Some folks having the same issues with their own rifles of these types simply had their receiver faces squared up with the barrel tenon thread axis then shimmed the barrel fit to the receiver so they clocked in the same keeping headspace and sight base holes aligned properly. Those barrels never walked point of impact any more as they heated up. But they still required a couple foulers be fired to even up the bore and groove surfaces so bullets fired afterwards shot more accurate.

Being the first person to complete the 50-shot high power National Match Course in the USA with the 5.56 NATO round in an M16, later that day some of us doing that at the 1971 Nationals discussed point of impact change as their barrels fouled and heated up. None of us observed any point of impact change as those barrels heated up nor went from clean to fouled. A couple of US Army, USN and USMC Rifle Team members shooting their M16's mentioned their rifles' accuracy got a little bit worse towards the end of their 20-shot string at 600. But all the services had a few issues with those Mouse Guns when they first went into competition.

"Newbies" showing up for their first and subsequent matches at the longer ranges with properly fit top quality barrels in their actions were never seen by me having to come down on their sights as their clean barrels get fouled from several shots. With factory rifle's match barrels, maybe 1 MOA at the most, but never 7 MOA which is what it takes to put center aimed shots over the top of a 6-foot square paper target at 600 yards. I've been there and done that. Neither does anyone else ranked at the top of the classification system in all the countries having high power rifle matches at all ranges using the same type of hardware. I too, have been there and done that observing what happens as well as participating in it.

Barrels that ain't uniform and smooth in their bore and groove dimensions will scrape jacket material off bullets until those low spots fill up with copper, Then subsequent bullets will shoot accurate 'cause no jacket material's scraped off unbalancing them.

Barrels that change point of impact as they heat up are usually those fit to unsquare receiver faces and/or are not properly stress relieved. This is common with most factory sporter rifles as there's one point around their tenon shoulder that's hardest against the receiver face at a high point creating a stress line there. Large numbers of folks start out with good quality properly fit cold barrels in competition at long range and see no more than 1/4 MOA change in point of impact which is usually caused by increased fouling in the barrel increasing pressure and bullets shooting out a tiny bit faster. This has been my experience (as well as many others) wearing out over a couple dozen 30 caliber barrels made by Hart, Obermeyer, Kreiger and match 7.62 NATO Garand barrels from the government's Springfield Armory.

In contrast to the above for centerfire barrels, rimfire barrels are different. Smallbore competitors well know that a squeaky clean barrel shoots their first shot about 3 MOA high. After a few "foulers" they'll walk down then stay zeroed to point of aim. Clean rimfire barrels have been chronographed faster than the same barrel and ammo 5 shots later from clean.
 
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What are you hunting and at what range? I live in Michigan, and most of the time white tail deer are at less than 100 yrds. Even if they are farther out I am not concerned with poa being slightly different. If I were taking shots consistently over 200+ yrds, then my concern would be different. On the other hand when I am crow hunting and taking long shots with 223, I will drop the cross hairs down a tad bit with a clean bbl.
 
The rifle will be used mostly for deer, most shots being inside 100 yds but occasionally as much as 200. I might also try some coyote hunting. I have only taken the rifle to the range once, and the next time I will compare my first shot with the bore clean to subsequent fouled shots. At this initial sighting in session I was getting sub-moa groups. I think if the difference is no more than 1 moa I can hunt with a clean bore. Thanks to everyone for sharing your experience to help me get started right with my .270 .
 
Living in the arid west, I have found that cleaning my hunting rifles is somewhat over rated! I do as was suggested in an earlier post to this thread, clean them once a year before sight in then leave them alone till the season is over. If I get into some rain (I sure wish:D) or snow, I take them apart and oil them. thats about it!
 
Dirty bores go hunting.


And... I'm one of those people that believes that certain factory bores might actually need some copper fouling to shoot reliably. So, I don't use copper removers, unless I've seen accuracy degrade considerably.


The only problem with trying to keep a dirty bore, is that we often get rained on or snowed on, during the Elk hunt. To dry the bore out, you have to do something. So, I usually make one pass with an under-size bore snake*, to keep from removing too much powder residue. It does change the POI just a bit, but not as much as a squeaky-clean bore.
(*such as a .277" snake in a .308" barrel)

Afterwards, if I think I'll be needing to make a long shot, I'll fire a single fouler.
 
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