What happened to my load?!

[Mram10us]

What's a OCW?

Optimal charge weight. Just a method for guys with short ranges to find a good load. YouTube is your friend

 

[Frog4aday]

Could it just be a wind issue? Good group was fired on a dead calm day and the poor group was fired on day with some wind? Heck, wind could have been 10mph both days, but good day was headwind & bad day was crossing wind? Just a thought. If barrel is clean & you were meticulous w/your loading process, maybe gun & ammo aren't the issue. Wind can be the devil.

 

[101stCurrahee]

There was a little bit of wind the second day. But that big of a difference at 100 yards?


The takeaway I got from this thread is worry about neck tension and try the process over with less charge. I wish it wasn't almost $3 a shot to figure this out.

 

[mountaincarver]

I shot 50 rounds through it new, Shooting once clean once 5x then shoot 5 clean once for rest of the 50. I then shot 30 more (in groups of 3 at different charges) working up my load where I shot the pictured group at 77 grains. At 77.5 grains it widened up, and I stopped at 78 grains even though I still had no signs of pressure.

So at that point I had 80 rounds through. I then loaded up these 20 more that were garbage at the same charge weight. So now I'm at 100 total.

Your not alone. you will find a load. the gun shot good and it will do it again. this has happened to me about 4 times now and I now expect it rather than pull my hair out. the bottom line is if the barrel is new, it wont shoot the same as a barrel that is broke in. regardless of how many rounds you think it takes to break one in, it wont shoot the same till it is broke in.. I just experienced this with a new one. shot great first time out after firing and cleaning. then changed. now wont even shoot the same bullet powder combo well, but it does have a node with it. by changing things up im back in the saddle.
anyway, one thing I am questioning about your post is did you take that rifle out to load test when it was clean after shooting 5 clean once. you probably know where im going here. if that was the case, it absolutely explains things.
lot of opinions on barrel cleaning but from my experience fouling is your friend. get about 10 rounds down, then start load testing, let it go for 80 or so. unless the barrel gathers copper, it will clean up just as easy as if only 10 rounds went through it.
bottom line is I believe your load test was done while your rifle was in a changing condition perhaps a little bit of new wearing off while the barrel was in the process of fouling up. regardless if this is the reason, it happens to me with every new one.

 

[Deputy819]

I sat at the same bench shooting off a sled for all but a couple

When I quit using a "sled" and did ALL shooting off of protektor sandbags I noticed much greater consistency out of my rifles. A sled does not allow your rifle to recoil naturally/consistently. Just something else to think about....

 

[cajun]

I would not work up loads in new brass. Once the brass is fire formed the capacity changes. I would also clean all the copper out then shoot a couple fowlers before load development. Did you weight sort the new cases. There could also be a difference in case capacity if the spread was high. What brand of brass?

 

[mpayne]

canjun- go to youtube and watch Panhandle Precision video series on new brass prep!

 

[101stCurrahee]

My barrel was clean before I started testing my loads, but like I said I started with a super low load (like 71 grains) I had no intention on using so it go plenty fouled before I got the the more useful nodes/loads. This is a field gun. Now that it's broken in I won't be cleaning it unless accuracy suddenly drops.

I would not work up loads in new brass. Once the brass is fire formed the capacity changes. I would also clean all the copper out then shoot a couple fowlers before load development. Did you weight sort the new cases. There could also be a difference in case capacity if the spread was high. What brand of brass?

I know shooting is expensive but you really **** away hundreds of dollars just to fire form brass before even starting? I think fire forming 200 rounds would cost me around $600 in components(of course it won't be so much reusing fire formed brass next time).

That really stings. Not to mention the barrel life of a 300 win mag is what, 1500 max? That's a lot of barrel life used up just to form some brass :/

 

[101stCurrahee]

I didn't know that was a no no word ... "Pee pee."

Haha....

 

[brentc]

My barrel was clean before I started testing my loads, but like I said I started with a super low load (like 71 grains) I had no intention on using so it go plenty fouled before I got the the more useful nodes/loads. This is a field gun. Now that it's broken in I won't be cleaning it unless accuracy suddenly drops.

I know shooting is expensive but you really *Rule 4 Violation* away hundreds of dollars just to fire form brass before even starting? I think fire forming 200 rounds would cost me around $600 in components(of course it won't be so much reusing fire formed brass next time).

That really stings. Not to mention the barrel life of a 300 win mag is what, 1500 max? That's a lot of barrel life used up just to form some brass :/

Instead of fire forming hundreds at a time, cycle 25 cases at a time. Once those 25 are done move on to the next 25.

The first thing I would do, though is take your fire formed cases and rework your load. Once you have your new load, use it to fire form however many cases you need. What you'll find when you're barrel is settled is that loads worked up with fire formed cases will transfer to virgin cases minus a few fps.

 

[Deleted member 107796]

+1 on 3 shot groups not sufficient for statistical significance, unless you're eliminating shooter error with a mechanical mount, like a lead sled or you're a master shooter.