Velocity?

[KyShooter74]

I’m sure this is normal but want to make sure. I cleaned my rifle it took 7 shots for my velocity to stabilize. The accuracy came back much sooner is this a normal thing I need to keep track of ? Will it take the same amount of shots for this to happen every cleaning or will this new barrel settle down and stay more consistent?

 

[KyShooter74]

I’m new at this so bear with me.

 

[Kadams1563]

My experience has been 3-4 shots for accuracy to return.

None of them are way off though just a slight zero shift until it settles down.

 

[KyShooter74]

Yeah I’m use to a few fouler shots for groups to settle just was never as worried about consistent velocity. Is this normal for the velocity to need to settle also?

 

[Doom]

When I used Gunzilla I found that it only took one shot to get the accuracy back. Since going back to Hoppes, I expect it to take maybe 3 or 4 since there will be more of an oil film.

 

[ShtrRdy]

The OP is asking about velocity settling in to the expected range. I don't know the answer to this. Would you mind posting the velocity readings you got from clean barrel to settled barrel?

 

[Kadams1563]

I recall that it tends to speed up a little during those few rounds due to laying copper back down and sealing up the barrel imperfections. It’s nothing drastic though.

You could also have a first shot higher in velocity if you ran a oiled patch down the barrel.

It’s never been anything I worry about. If I’m doing load development I shoot 3-4 rounds first and then start my velocity testing for data.

 

[morganlamprecht]

from my experience, the speed difference is from any liquid residue being left in the bore

if i clean and finish off with an oil patch in my current 6.5 creed barrel, bullets with come out around 2830-2850 and slowly speed up to normal in the first 3-5 rounds, they settle @ 2875 fps

if i clean and finish off with a patch of acetone or alcohol, the first shot is within 10 fps of the average

did the same with my 6.5 prc...leaving anything in the barrel leaves velocity about 50 fps slower...running an acetone patch first, speed falls in line from shot 1

couple other local guys checked this on their rifles and found similar

 

[Steel head]

from my experience, the speed difference is from any liquid residue being left in the bore

if i clean and finish off with an oil patch in my current 6.5 creed barrel, bullets with come out around 2830-2850 and slowly speed up to normal in the first 3-5 rounds, they settle @ 2875 fps

if i clean and finish off with a patch of acetone or alcohol, the first shot is within 10 fps of the average

did the same with my 6.5 prc...leaving anything in the barrel leaves velocity about 50 fps slower...running an acetone patch first, speed falls in line from shot 1

couple other local guys checked this on their rifles and found similar

I've noticed the same.

 

[KyShooter74]

The OP is asking about velocity settling in to the expected range. I don't know the answer to this. Would you mind posting the velocity readings you got from clean barrel to settled barrel?

I’m getting 2885 ish after cleaning this is a new barrel mine you. It started at about 2830 and speed up with each shot until I got to 7 then flattened out and got 5 that read 2885 and 1 that clocked 2887.

 

[KyShooter74]

Ne

from my experience, the speed difference is from any liquid residue being left in the bore

if i clean and finish off with an oil patch in my current 6.5 creed barrel, bullets with come out around 2830-2850 and slowly speed up to normal in the first 3-5 rounds, they settle @ 2875 fps

if i clean and finish off with a patch of acetone or alcohol, the first shot is within 10 fps of the average

did the same with my 6.5 prc...leaving anything in the barrel leaves velocity about 50 fps slower...running an acetone patch first, speed falls in line from shot 1

couple other local guys checked this on their rifles and found similar

never crossed my mind to strip the residual with acetone or similar. Will start doing that I just push the patches until they come out dry and clean.

 

[Kadams1563]

from my experience, the speed difference is from any liquid residue being left in the bore

if i clean and finish off with an oil patch in my current 6.5 creed barrel, bullets with come out around 2830-2850 and slowly speed up to normal in the first 3-5 rounds, they settle @ 2875 fps

if i clean and finish off with a patch of acetone or alcohol, the first shot is within 10 fps of the average

did the same with my 6.5 prc...leaving anything in the barrel leaves velocity about 50 fps slower...running an acetone patch first, speed falls in line from shot 1

couple other local guys checked this on their rifles and found similar

Thanks for this. I would have thought an oily barrel would have caused higher velocity but I guessed wrong.

 

[KyShooter74]

Thanks for this. I would have thought an oily barrel would have caused higher velocity but I guessed wrong.

Me also that’s why i asked, it threw me off when they clocked slower vs faster.

 

[morganlamprecht]

We were originally thinking the same thing also, but I’m guessing oil/liquid allows the bullet to slide easier building less pressure? Idk the science...

I am for sure We tested it multiple times on my 6.5creed and 6.5prc, another guys 6brx and another 6dasher....that was consistent enough for our work lol

 

[Deleted member 10043]

It's normal after cleaning.

 

[KyShooter74]

We were originally thinking the same thing also, but I’m guessing oil/liquid allows the bullet to slide easier building less pressure? Idk the science...

I am for sure We tested it multiple times on my 6.5creed and 6.5prc, another guys 6brx and another 6dasher....that was consistent enough for our work lol

After a bit of thought it makes perfect sense in that aspect. Lubrication equals less friction which helps in raising the pressure as the bullet travels.

 

[Deleted member 10043]

That is why they are called fouling shots.