What happened to my loads?

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laker415

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So I just got back from the range and my remington 700 5R milspec in 223 really threw me for a loop today.

I was working on some loads with varget and 75 grain amax. I had previous luck with a load involving these components so I wanted to play a bit more and see if I could get it tighter.

Needless to say not one group was worth keeping. I could get 2 or 3 somewhat close and then 2 would be way out in left field. I checked my setup and everything was tight. I thought it might be me but I was punching ragged holes with my 308.

The gun received a thorough clean not long ago and last week I putabout 60 rounds through with far better results, including some factory loads. I am just at a loss as to what happened. I am tempted to load some more of the charge that worked last week and give it another go. Sorry for the long post but any advice on what could explain this would be appreciated. Thanks



Not sure if this would explain my day, but this batch of brass had been full length resized as I was having some chambering issues last time and wanted to ensure this would be fixed. This is the first time I full length resized as I usually just neck size.
 
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Ganderite said:
It would help me to understand if you gave all the particulars of the load that worked and then what was different about the bad group ammo.
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Without my notes in front of me, I think the charge is 23 grains of varget under a 75 gr A-max in a hornady case with a federal small rifle match primer. Didn't change anything from the previous week other than full length sizing the brass

Went up in .3 grain incriments from there and I just couldn't get them to group. Called it quits halfway to not waste what was left.
 
I use 26 gr of Varget with 80 gr bullets in my rifle with a 1:8 twist. Your load is only .5 gr over Hogdon's starting load for 75 gr bullets and Varget powder. You might have better luck with a hotter load, but you should work up to that watching for pressure signs as you go.
 
I realize it's a low charge. I was just using info from my lyman book. I always work up safely, I was just surprised at how much worse they were getting. It was putting up the worst groups I have seen out of it.
 
I had the same problem with an A-Bolt 7mm-08 years ago.

It put the first 3 rounds in the same hole then started to open up. Realized after a couple shots that the scope was moving around - D'OH! This never happened again after it was fixed, but the next time I got to the range it did the same thing again - first few shots making cloverleafs, then started to open up...action screw had rattled loose. @^%&#**!!! Once that situation was remedied, I couldn't get the rifle to group like it had previously with an identical load. Talk about the height of frustration.

It wasn't until a gunsmith suggested to me that I might have copper fouling. Went out and bought an Outers Foul Out II system and I couldn't believe the results. From what you've said, it sounds like your rig is tight, so this might be worth looking into. I scrubbed the bore on this rifle with everything under the sun until I could swear on my mother's grave that it was 100% free of any fouling. When I hooked up the Foul Out system, there were literally chunks of copper that came off. I couldn't believe it.

Not sure this is your problem, but might be worth looking into. On another note, how far off the lands does your OAL have the bullet? I found out the 7mm-08 A-Bolts of the time had excessively short throats and could be pretty finicky with seating depths.

Again, not 100% sure of the source of your issue, but some ideas to ponder. Hope it helps.

SS



PS - This all took place 20 years ago before I'd ever heard the term "barrel break-in" as well. The CGN jury still seems to be out on that line of thinking, but for the record I hadn't gone through any particular kind of break-in with that rifle.
 
You went up in .3 grain increments from there to where? 25.0 is max.
How you size shouldn't change group sizes. Changes in humidity or other environment conditions might though. Any loose screws? Same powder lot?
You only anneal when it's required. Annealing is not required every time.
 
Brass is on firing 4. I don't anneal. Neck sized every time except for this last time. Made it to the 5th charge weight before I gave up so that's 1.5 grains higher than starting charge. I used a copper cleaning solvent last cleaning and spent a lot of time working on the bore until the patches were clean. Gun probably has 300 rounds total through it. I will check the action screws but I know the scope is tight.

I will just have to try again on my next days off in 3 weeks.
 
I'm shooting the same bullet powder combo as you. I've had a few wtf issues with it, just as any other chambering. If my groups are opening up it's usually caused by a fouled barrel or bad brass. I have had to tighten action screws before as well, bedding solved that problem.
 
Were the 2 shots that are off from the other ones, still together? or just random?
Usually when it shoots 2 groups at the same time, and goes back and forth, its a bedding issue/rocking on something.
 
I shoot the same combo. 25.0 Varget pushing the 75 A Max, any of the CCI SR primers as they seem to make little difference between them. Hornady brass. Anywhere between 24 and 25 is where you want to be, below that I'd consider strictly work up territory.

What's your run out and seating depth? VLD bullets can be tricky to seat well and they like to be at or jammed into the lands. .015" jam is the place to start. They're also sensitive to run out. Maybe the FL sizing introduced run out into your cases? Did you measure case neck run out before and after sizing? What dies are you using?
 
I had terrible luck with 75 AMAX in my 1in8 twist .223..very erratic. Switched over to Hornady 75gr HPBT or 80gr SMK's and its a night and day difference. Im shooting 24.4 gr of Varget..seems the faster i push the bullet the tighter and more consistent my groups are. I never neck size either..see no benefit in accuracy.
 
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About the only design flaw on the Remington 700 action is the front bedding screw that is drilled and tapped through the action. This will allow cleaning solvent to seep down into the bedding or between the action and the stock. One little drop of oil will cause the groups will open up. Taking the action out of the stock and making sure that is clean and dry every time you clean it may solve a lot of problems with bigger groups. It also makes sure you tighten your bedding screws to spec each time you take it apart.
 
maynard said:
About the only design flaw on the Remington 700 action is the front bedding screw that is drilled and tapped through the action. This will allow cleaning solvent to seep down into the bedding or between the action and the stock. One little drop of oil will cause the groups will open up. Taking the action out of the stock and making sure that is clean and dry every time you clean it may solve a lot of problems with bigger groups. It also makes sure you tighten your bedding screws to spec each time you take it apart.
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What is the torque value for the action screws?
 
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