Load testing question

[its only light]

Hey everybody thank you so much for all the advice on testing and bedding! I floated the tang and relieved the lug. I also used bags instead of my bipod. My smallest group last time was my largest group today. My best today was a .250 group with 53.0gr of rl17 at 3029fps. I was happy to say the least!!!! Now hopefully I can get it to do that every time.

 

[its only light]

Searcher,

I really wish I would have read your post yesterday before I did the relieving of the bedding. After hearing that I'm thinking maybe free floating the tang would have been sufficient. I will know for next time. My trip to the range went way better this time so I'm not to disappointed I did it though. Thanks again to everybody!

 

[BoydAllen]

IMO the primary reason for clearance at the bottom front and sides of the lug is that with a tight fit all around is is very easy to scrape off a bit going together, and have it act as a spacer under the lug, that interferes with with the action bedding making solid contact. Also, I think that the reason that folks don't do this is pure laziness. It takes time to open a mortise where needed and tape the lug. Also, I have some extremely good shooting rifles and none of them have any part of the barrel bedded. I think that this practice came about when fellows were shooting for 1MOA accuracy when building hunting rifles based on Mauser actions, and it developed a life of its own. This is not to say that a rifle will always shoot worse with the barrel bedded, just that based on plenty of results with more modern actions, such as yours, it does not seem to have any advantage.

Congratulations on you success! Keep up the good work. Next time out, do a little dry fire practice. It may help to make those quarter inch groups repeat more often. As the size of your groups decrease, I think that you will see the influence of factors that get lost in the noise when dealing with rifles that have less potential.

 

[amlevin]

IMO the primary reason for clearance at the bottom front

I had a very accomplished BR shooter and gunsmith tell me that without clearance below the lug, expansion from heat can cause the barrel to be pushed up more. Just a slight amount which alters the stresses within the action (as the action screw is pulling the other way) which in turn causes increased group sizes.

I can see lack of clearance on the sides, coupled with any taper of the recoil lug, doing likewise. It may be only a minute fraction of movement but the stresses induced are another variable added.

 

[wapiti25]

You do need to be aware that primers can change the vertical more than some think. I would look for a std or milder primer to test. In shooting long range shooting (600 and more) vertical will "kill" your score by going high and then low out of your aiming point. I like the Fed 210 and the Wolf/Tula but I have not used any of these with the H100V, I have used them mostly with single base extruded powders. Good luck