Cold bore shot impact?

Hello, there are several possible issues here, but not quite enough information provided to come to any one specific conclusion as to what the problem could be. What range were you shooting at? Who made the action you are using? Who installed the barrel onto the action? What caliber is the rifle chambered for? Who reamed out the chamber for whatever cartridge you are using? What is the twist rate for the barrel? (When answering the above questions do not name a specific person. Simply say something like, I did, a local experienced gun builder, a local experienced gunsmith, a nationally know gunsmith shop.) However be specific on the action and barrel information. In regards to the new stock who bedded the new action into the stock. How was it bedded? What type of rail "0" MOA, "20" MOA or other. Who made the scope rings? Who made the scope? Who mounted the scope? and more importantly what type ammo are you using and is it factory, and if so which brand. If it is hand loaded what bullet are you loading into it. Seems that these are a lot of questions, and they are but all necessary to know before one can even begin to troubleshoot your issue.

Ammo can be a big issue. As an example I was asked to try out some copper bullets in 30-06 for a friend. I was using my Tikka T3X at 100 yards. This rifle will shoot 0.7 MOA or less with Nosler, Sig Sauer or Federal 165 grain factory ammo. My hand loads will not really shoot any better than that. I have hand loaded Barnes TSX 165 gr copper bullets that would group at 0.8 MOA or less. My friend supplied the copper ammo that he wanted to test. In this case it was Federal Premium 30-06 Trophy Copper. Keep in mind that this rifle was shooting sub MOA with just about any cannon fodder put through it. From a bench at 100 yards on a calm sunny day with at temperature of 38 degrees the first shot out of the barrel did not even hit a 24" target backer much less the target. The second shot was no better. A walk down the range confirmed no hits on paper. Keep in mind this rifle shoots 0.7 MOA and was not hitting anything. I taped 4 of the 24 inch target backers together and a target dead center giving me 48 inch x 48 inch target area at 100 yards. The first shot hit the lower left edge of the backer. The second shot hit the top middle of the backer again near the edge, the third shot clipped the bottom of the backer at 6 O'Clock. The three shot group was some 23 inches. Suspecting that maybe something went wrong with my scope or other issue with my rifle i then loaded Federal Premium 165 gr Trophy Bonded and fired a three shot 0.8 MOA group 1.5 inches high, which is where I had the rifle sighted in. Tried another 3 shot group with the trophy copper with the same results as the first 3 shot copper group. The conclusion drawn from this exercise is that for some reason my particular rifle did not like the Trophy Copper and simply sent them off into space going whichever way they wanted to while liking the Barnes TSX copper just fine. Now another conclusion that can be drawn is that it doesn't have to necessarily be anything wrong with the rifle to cause a scattered group, it just doesn't like the ammo. I have 5 hunting rifles .308, .270, 30-06 and 300 WM. All of them will group sub MOA shooting either 3 to 5 shots rapid fire at 100 yards. Each has it's own pet load, either factory or hand load to accomplish this. So before you get all concerned about your rifle, try some different ammo. And yes please answer the questions at the beginning of this missive. As it is said, "Inquiring minds want to know."
Range was 100 yards. Action is Long Action Rem 700. PacNor put barrel on the action. 257wby 1-10 twist. New stock has not been bedded. I dropped barreled action into HS precision stock and torqued to HS recommened torque of 65 in/lbs. Scope is Leupold. Rounds were handloads that have shot in the rifle prior to swapping stocks.
 
That is incorrect or at least incorrect with most rifles.
Until you have fired a shot from a cold clean bore, then cleaned the bore and allowed it to completely cool and followed that procedure for five successive shots then you have not experienced the real issue with a cold clean bore shot. The gun, assuming it is an moa or better gun will group the shots together. Then after the fifth shot shoot five more in succession with out cleaning and you will see the group move to where a warm fouled barrel shoots. I have personally observed this during range exercises on a number of guns fired by different people. The cold clean bore shot seldom if ever falls in the group of the warm fouled barrel.
 
Until you have fired a shot from a cold clean bore, then cleaned the bore and allowed it to completely cool and followed that procedure for five successive shots then you have not experienced the real issue with a cold clean bore shot. The gun, assuming it is an moa or better gun will group the shots together. Then after the fifth shot shoot five more in succession with out cleaning and you will see the group move to where a warm fouled barrel shoots. I have personally observed this during range exercises on a number of guns fired by different people. The cold clean bore shot seldom if ever falls in the group of the warm fouled barrel.
What you said is this:

The short answer is no. For the cold bore shot to be predictable it has to be shot from a cold clean bore.

It is not true. Any shot fired when the bore is at ambient temperature is a cold bore shot.

A cold, clean bore shot is an animal of a different color and stripe.

The only way have that CCBS remain consistent is to clean after every shot.

Yes, groups usually move after the CCBS, that's why you fire some foulers, let it cool, Re-zero and you will find that as long as you're not doing any high volume shooting, that zero should remain consistent at least for the Duration of the season.

My experience and everything I've read from people I trust is that 3-5 foulers through the bore is the sweet spot.

Of course one way to bugger that up is to keep shooting shots beyond those listed because that dirty bore will continue to build up material and at some point it's going to move your POI again.
 
Range was 100 yards. Action is Long Action Rem 700. PacNor put barrel on the action. 257wby 1-10 twist. New stock has not been bedded. I dropped barreled action into HS precision stock and torqued to HS recommened torque of 65 in/lbs. Scope is Leupold. Rounds were handloads that have shot in the rifle prior to swapping stocks.
Before you waste time and ammo, which relates to money get the stock bedded to the action. An improperly bedded stock allows movement between each shot making any kind of accuracy virtually impossible. Ran into this issue with two factory new Winchester Model 70's back in the early 70's before Winchester started glass bedding the actions and floating the barrels. In both cases 100 yard groups went from 4 to 5 inches to Sub MOA after bedding and floating.
 
What you said is this:



It is not true. Any shot fired when the bore is at ambient temperature is a cold bore shot.

A cold, clean bore shot is an animal of a different color and stripe.

The only way have that CCBS remain consistent is to clean after every shot.

Yes, groups usually move after the CCBS, that's why you fire some foulers, let it cool, Re-zero and you will find that as long as you're not doing any high volume shooting, that zero should remain consistent at least for the Duration of the season.

My experience and everything I've read from people I trust is that 3-5 foulers through the bore is the sweet spot.

Of course one way to bugger that up is to keep shooting shots beyond those listed because that dirty bore will continue to build up material and at some point it's going to move your POI again.
I actually agree with Wild Rose to a point. It has been my experience over 50+ years of shooting both competitively, teaching and simply plinking that there is no such thing as an accurate cold - clean - bore. Even if cleaning after each and every shot the POI will vary simply because of the residue from cleaning that is going to make the bore of the rifle inconsistent. In competition across the National Match Course for many years as well as long range at 600 to 1000 yards with both Service and conventional match rifles a clean bore will not shoot accurately.
Rifles used in competition are almost never fired with a clean bore. At the beginning of the match there are sighting rounds, usually two shots that are not only used as sighting shots but also used to foul the bore, burn out any of the residue from cleaning solvents and preservative oils left even after running clean patches down the rifle bore. Some competitors when shooting across the course will fire the first 60 rounds prior to the 600 yard stage without cleaning, then do a brush clean (run a dry brush down the barrel) to expel the accumulation of debris out of the barrel . At 600 yards one is still allowed 2 sighting rounds to which in turn again foul the bore then fire 20 rounds for record in 20 minutes. This is not anywhere close to a cold bore. If one is not shooting a cold clean bore then one might find that the difference between a first shot hit and a group of 3 or 5 shots from a cold to hot barrel will not vary enough to interfere with a 1 MOA or less group. I never group my rifles with a clean bore. They all are fired with at least two to four fouling shots prior to sighting in. I start with a cold fouled bore then shoot a group of 3 to 5 rounds (Whichever the magazine will hold) as fast as I can comfortably shoot accurately. The net result is that all of my rifles shoot 1 MOA or less groups no matter whether the barrel is cold or hot. The result has been over the last 45 years or so, one shot has led to one dead deer from a cold fouled bore. Sorry can't comment on follow up shots other than at the range since I live buy the rule of US Army Instructor/Competitor Lones Wigger, "One shot one kill." By the way his firearms collection is up for auction. Something for all of you to think about. All of his firearms were and still are, "SHOOTERS!"
 
I have a nice little group of about 1" shot with my 6.5x55 Tikka. One inch you say, not so great. But I shot it over 5 successive trips to the range. On different days. Always at ambient temp, current wind conditions. First shot, bore with at least 3 rounds down at the beginning. More later.

That is the test of hunting rifle accuracy of first shot. IMO
 
I have a nice little group of about 1" shot with my 6.5x55 Tikka. One inch you say, not so great. But I shot it over 5 successive trips to the range. On different days. Always at ambient temp, current wind conditions. First shot, bore with at least 3 rounds down at the beginning. More later.

That is the test of hunting rifle accuracy of first shot. IMO
Yes!
 

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