lod development on a brand new gun

[42769vette]

ive heard it said that a gun doesn't reach max speeds until its broken in.

if thats the case do you bother doing load development on a unfired gun or do you put some rounds down the pipe before you bother finding the perfect load.

 

[Longshot38]

Re: lod development on a brand new gun

Fire about 5 fouling shots. Then start load development. Barrel Break-in is a myth.

 

[MitchAlsup]

Re: lod development on a brand new gun

Go buy a lot (100) cases for your favorite brand. Then laod them up and shoot them in that gun with a moderate load. Then clean the gun up, making sure you get the copper.

Finally, start load development with those fire formed cases.

 

[flashhole]

Re: lod development on a brand new gun

Break-in wasn't a myth with my Kimber Longmaster Classic. It took about 200 rounds down the barrel before it really came into its own. Groups went from about 1.2" down to 0.2". Mostly what I get now that it's broken in is one ragged hole. I scrubbed it clean after every 50 rounds. I kept shooting the same brass with the same load.

 

[ChadTRG42]

Re: lod development on a brand new gun

vette,

Several new rilfes with custom barrels I've seen take about 150-200 rounds before you get your actual true velocity. My 260 with a Bartlein barrel was running about 120 fps slower than normal when brand new with the load it liked. After about 150-200 rounds, the velocity came in where it should be, and has remained there. The load itself didn't change. The accuracy stayed the same, but the velocity increased. Hope this helps.

Chad

 

[Greg Langelius *]

Re: lod development on a brand new gun

While barrel break-in may or may not be a myth, I'm pretty sure that assumptions that one load will be tried and true for the life of a barrel most assuredly is a myth.

Things change, bores among them, and these changes will eventually end up altering the load's bore transit time. Between this and throat erosion, it may make sense to do a little bit of load 'adjustment' development from time to time, especially if the barrel seems to have 'gone sour'.

Greg

 

[KQguy]

Re: lod development on a brand new gun

I agree,I had to tweek my load a few weeks ago,on my 7mmWSM.I have 1600rds down it,and noticed accuracy was starting to slip.So I ran them through the chronograph,and realised my velocity was down about 50fps from when I developed the load.So I added powder until I got back to my original velocity,now it shoots as good as the day I developed it.I am still using the same components as I was when I developed it,because I buy in bulk(powder,primers,cases etc.),so something in the barrel changed(probably throat erosion).

 

[42769vette]

Re: lod development on a brand new gun

thanks guys this is the info i needed. i ended up loading up 10 rds at minimum powder and shot them and cleaned between shots. i dont use a bore sighter so this also got me on paper for load development. i usually buy used guns so ive never thought about velocity gains after the barrel was broken in so i didn't know what sop was on it. thanks