Clean vs. Dirty vs. Cold bore

[lancetkenyon]

Ask yourself what effects accuracy the most.

 

Cold bore? Clean or fouled.

Clean bore? Cleaned of all carbon and copper, light oil patch chased by 3-5 dry patches.

Dirty bore? Of course not like dropped in the mud of full of spiderwebs, but fouled, maybe even 100+ (or more) rounds without any cleaning.

 

Let's say, across the board, factory and custom barreled rifles. Not a junk rifle that wouldn't hit the dirt if you dropped it, but any number of factory or custom rifles.

 

How much difference can any of these conditions (clean, dirty, cold bore) cause for a gun that normally shoots MOA or better?

 

How do you take a rifle into the woods for hunting season? Clean? Dirty?

 

I have always tested this with my rifles, with factory and high quality barrels.

 

I tested it this weekend with my new 6.5 SLR. After 107 rounds for load development, and misc. shooting, I had 3 very accurate loads worked up for various activities.

 

1. Target shooting at steel/paper. 140 Berger HVLD @ 2780fps.

2. Hunting. 140 Berger HVLD @ 2900fps.

3. Misc. 142 SMK @ 2880fps. (I was testing them against the Bergers)

All 3 loads impact in the exact spot at 100 (1.5" high) & 200 yards (0"). I can dial back .3mils on the scope to get me 1/2" high at 100 yards.

 

All of these rounds shoot amazing.

 

So after 107 rounds, I thoroughly cleaned my rifle in preparation for a lot of shooting and hopefully some hunting too. Took every bit of carbon and copper out of the barrel (which there was very little copper that came out of the Bartlein that I noticed. Once several patches came out completely clean with Shooter's Choice MC#7 bore cleaner, and also with Shooter's Choice copper remover, I ran an oiled patch down followed by 3 dry patches as I have always done.

 

Well, this weekend, I got to the range to sight in my new scope (Kahles K624i=amazing). I started off with 50 rounds of .223 to warm up so as not to induce "cold shooter" error as much as possible. I had bore sighted it at home, and again at the range, and first shot had me dead on elevation @ 100 yards, and about 5" left. made the correction and started my test to see what, if any, difference a clean bore would make to my accuracy.

 

The results might surprise you.......I will post group photos later this week, in order of shot number.

 

Let's see what you all think. Take the poll please.

[muledeerarea33?]

Voted on my results, can't wait to hear what you came up with on your rig.

[lancetkenyon]

I need to make one clarification. In the poll, if it states "does ______ effect accuracy", I mean in a negative or detrimental way.

 

Of course it is going to effect it one way or the other......

[khmer6]

Shoot it fouled!

[lancetkenyon]

Shoot it fouled!

How many shots is "fouled" after a thorough cleaning?

[kwp]

I've found after 20-30 rounds accuracy drops off a little so I clean after every time I shoot. One fouling shot and my most accurate shots are usually #2-20.

 

I use boretech products to clean until there is no copper left.

[rossislider]

I haven't done nearly as much experimenting as you, but I have noticed my groups tend to tighten up after 3-4 fouling shots have gone down a clean barrel.

My normal pre-hunt routine is to get all my sighting in and practicing done, clean the barrel, fire 3-4 fouling rounds, and put the rifle away till hunting time.

 

I like to carry a bore snake with me in the field for light cleaning should I get dirt or something in the barrel, but that is it.

[DAS]

Clean it when accuracy drops off. With my factory barrel Remington 700 7mm mag it takes a couple fouling shots to get settled in then it's good to about 120 rounds. Two years ago I hunted with about 100 rounds down the tube since last cleaning.I don't believe cleaning your barrel is as important as some people think it is, unless your particular rifle needs it.

[lancetkenyon]

Good results so far, keep them coming.

[lancetkenyon]

Here is a photo of how my rifle shot prior to the thorough cleaning and testing. 3 shots at 200 yards. Granted, I am not sure if I can always shoot this well, but it shows what the rifle is capable of. I am usually in the .4-.6s @ 200.

[DesertBull]

200-300 rounds between cleanings for both my 7RM and .308.

 

2 fouling shots.

[firstcoueswas80]

My 257 wby strarts to fall off after 12-15 rounds. Not a bunch, but slowly. It shoots best clean clean CLEAN, and one fouler.

 

I haven't dialed the 7 LRM in yet, as I'm still looking for that stellar load.

[willhunt4coues]

I have found every rifle is different from when its READY to shoot.

 

I have too tested about everything i can even down to primer seating depth.

 

On one of my rifles Savage 6.5 CM Shilen sss match barrel 26" it can be clean or dirty and it still hits its spot perfectly.

 

Now my new rifle Shilen Custom 6.5 Shilen sss match barrel 26" it takes exactly 5 shots to be right on after a complete barrel clean. I usually shoot around 10 rounds so I know I have a good coating in the barrel. I then will take it out to 800 yards the next day. the first shot is always right on. Then i will try it again in the evening the following day at again 800 yards and again it is right on.

 

Every gun is different and have seen guns take up to 15 rounds to get right on (but those were factory barrels).

 

So try this next time you go out.

Set up your chrono and make a precise shot at 100 yards with a clean bore.

Foul the barrel out and the following day do the same test set up the chrono and fire at 100 yards,

Then make sure you take great notes and do the test multiple times to see what is going on.

 

I have also found out that the savage did the same thing my new rifle was doing until i hit around 300 rounds. So it may take a few more rounds to get her able to shoot cold bore, clean bore, and fouling perfectly. Then again it may never do it and it may take 5 to 10 rounds to be on. But once she is she should not change and if she does you may look at the rings/scope to see if there is a problem. Thats why I always ream my rings (same thing as lapping but A LOT faster) to make it as true as possible. I read an article that stated if you do not lap your rings your impact will shift as the gun sets over time.

[8OWHUNT247]

I clean my barrel every time I shoot EXCEPT right before I hunt, I do not want anything to change between the last cold bore shot and the hunt.. I am a weirdo though so it wouldn't surprise me if that was a bad idea, in any case, its what I do.

[lancetkenyon]

Here were my groups after a total cleaning. All were shot at 100 yards.

 

1st shot was a sighter (and not shown), then I adjusted accordingly and started shooting to see what groups would look like. I adjusted a bit between groups until I was satisfied.

 

Shots 2-5

 

Shots 6-10 (winds kicked up from left to right a bit, but were fairly consistent)

 

Shots 11-13 (winds kicked up a bit more)

 

Shots 14-16 (adjusted left .2mil)

 

Shots 17-19 (adjusted up .2mil,, right .1mil)

 

Shots 20-22 (adjusted down .1mil and winds slowed)

 

Shots 23-25

 

Shots 26-28

 

Shots 29-31 (This is the best group I have ever shot)

 

Here is the last group without the "on target" marks to see the elongated hole better.