Having trouble with 77gr tmk

[Warlok813]

So I worked up some loads for my 20" woa using varget. I went to do some testing working in .4gr increments from minimim charge. My standard deviations were atrocious most of the groups. Im talking from mid 30's up to 50's with 1 group going down to 11. I also shot some 60gr V-maxs on varget with similar results. Has anyone else had this experience? Using BR-4's and Frontier brass. Any input would be helpful because im scratching my head. Of course new as I am I dont have a lot of reloading experiance.

 

[Ryridesmotox]

Can you list more of your ammo specs? Base to ogive or overall length, how you're prepping brass, how you're measuring powder, all that jazz. Many more experienced loaders here than me will be able to help, but only if they know what's up.

I personally havent had as much luck with varget as everyone talks about. I have found pretty good loads with IMR4064 in 223 and 308 that are around 9 sd and 23 es... by total accident. I don't neck turn or neck size, I full length size, check case length and load it. So I kinda stick with that now.

You may want to switch powders to something else. But, without knowing your loading operations, it is difficult to say how you might be able to mitigate your velocity issues.

What was the group size like?

 

[Warlok813]

Can you list more of your ammo specs? Base to ogive or overall length, how you're prepping brass, how you're measuring powder, all that jazz. Many more experienced loaders here than me will be able to help, but only if they know what's up.

I personally havent had as much luck with varget as everyone talks about. I have found pretty good loads with IMR4064 in 223 and 308 that are around 9 sd and 23 es... by total accident. I don't neck turn or neck size, I full length size, check case length and load it. So I kinda stick with that now.

You may want to switch powders to something else. But, without knowing your loading operations, it is difficult to say how you might be able to mitigate your velocity issues.

What was the group size like?

Stainless pin tumble, loading right out to mag length for my ar, weighing every charge. Full length size, lee bullet seater, and a light crimp from the lee factory crimp die. No neck turning or anything. Had 1 group close to moa that had a sd of about 11 right about middle of the road for powder weight. The rest of the groups were 2" or so. I was to discusted to measure them so thats more of an estimation.

 

[Ryridesmotox]

Are any close to being full cases? Or have you not got to that point. My experience with varget is meh... but I did notice it improved as it got to compressed case capacity.

 

[Warlok813]

Are any close to being full cases? Or have you not got to that point. My experience with varget is meh... but I did notice it improved as it got to compressed case capacity.

They are all fairly full, the highest ones were slightly compressed. Tmk's seat deep cause of their length

 

[Ryridesmotox]

What velocities are you getting

 

[Warlok813]

 

[bschneiderheinze]

24 grains 8208 is what I will be trying tomorrow saw that load make hits out to 1200 yards might want to back it off for gas gun. I currently use 24,5 varget in my bolt and gas gun accurately.

 

[Warlok813]

24 grains 8208 is what I will be trying tomorrow saw that load make hits out to 1200 yards might want to back it off for gas gun. I currently use 24,5 varget in my bolt and gas gun accurately.

Seen a lot of people use 8208 with good results. I have had luck with varget in lighter bullets. Im actually suprised at how bad it treated the heavier ones. Maybe i should revisit just to make sure. Cant rule out operator error i suppose.

 

[Ryridesmotox]

The 8208 will probably treat you pretty well. I like that stuff.

 

[padom]

So I worked up some loads for my 20" woa using varget. I went to do some testing working in .4gr increments from minimim charge. My standard deviations were atrocious most of the groups. Im talking from mid 30's up to 50's with 1 group going down to 11. I also shot some 60gr V-maxs on varget with similar results. Has anyone else had this experience? Using BR-4's and Frontier brass. Any input would be helpful because im scratching my head. Of course new as I am I dont have a lot of reloading experiance.

Get some 8208XBR. Shoots amazing in every WOA barrel I've shot with 77smk.

 

[Steel head]

Varget was Meh for me.

23.something grains of 8208XBR with 75/77 bullets seems to shoot well for pretty much everyone.

My load for my Rainer Ultra match SPR barreled build is 23.4 with LC brass and a #450 primer loaded to a comfortable mag length.

Safe at any temperature and consistent at distance.

 

[Billl223]

From a 20" JP barrel. 24.0 8208, CCI BR4, Starline brass, 2850 fps, 9 Sd. No crimp, using Redding "S" die full length size.

 

[Dev L]

You can't fit 24 grains of Varget with a 77 TMK at mag length in a .223 case. It physically will not fit. With Lake City brass I end up at 2.255" to 2.259" OAL. You get a compressed load that is too long OAL and sucks for accuracy too but no pressure signs. You can run a max load of 8208 23.2 grains and not have pressure signs if you run less hot primers, minimal shoulder bump, OAL slightly over 2.250 (I had luck at 2.253"), or use lighter brass (more capacity). My barrel has accuracy nodes at 22.2 and 23.2 of 8208.

 

[padom]

Here's my 20" WOA SDM 1:7 223 Wylde rifle gas with 77smk and 8208XBR. All my WOA's love this load

OCW Test




Seating Depth Test




4x5 @ 100yds





500M (546yds)

 

[Warlok813]

Wits SD that high ( assuming you didn't mean extreme spread) I would bet your issue isn't powder or projectile but either brass prep or the crimp. How consistent is your shoulder bump? How consistent is your neck tension since you're crimping? Are you seeing copper shavings around the neck of the case after seating and crimping? Is your seating die leaving a detent in the projectile?

Also a SD of 15 on a gas gun ( you're running a gas gun right). with crimped brass isnt bad. You could tighten up the group by adjusting seating depth and maintaining your current velocity. Also, in smaller cases like the 223, small variances in charge weight can throw off your SD if you're not charging in the middle of a node.

Last, is you barrel a 1:8 twist or faster?

I am using a gas gun. And yes that is my SD I was thinking it may have possibly been my fault. Cant rule out human error. Im pushing my shoulders .002" with a possible .001 variation. My seating die isnt leaving marks on the projectile that I can feel or see. Ill admit im not sure how to test my neck tension after crimp. Im using the lee factory crimp die if that helps. No shavings on anything that I have seen.

 

[Warlok813]

Here's my 20" WOA SDM 1:7 223 Wylde rifle gas with 77smk and 8208XBR. All my WOA's love this load

OCW Test




Seating Depth Test




4x5 @ 100yds





500M (546yds)

Running the same barrel. Thank you

 

[Warlok813]

I'd bet it's just variation in neck tension. Run a ladder test, find a good velocity node, then tighten up your group by adjusting seating depth and shoot. Don't spend hundreds of rounds on load development

Would neck tension really result in such wild variations? And if you saw my picture earlier, I had one decent group with decent sd. Would it not throw all of them off. It seems that the one group is the exception. And they were all 5 shot groups. I would imagine in 5 shots at least one would have the same problem throwwing my velocities off.

 

[Warlok813]

You shot the test at 100 yards so SD variance won't show up as well as it would at say 400-500 yards. Neck tension can effect SD, but depending on the variance it may not effect it much. Once you start stacking inconsistencies such as neck tension, a tenth or two variance in powder and a few thousandths in seating depth, yes SD will really start to grow. Best and fastest way to find a load to minimize the impact variances will have at distance is to find a good velocity node and run it. In regards to your groups, have you ruled out any possibility of shooter error or inconsistencies that could have effected the group sizes?

As I said I cant rule out any human error. Are you suggesting that my high SD may not be affecting the large groups I encountered? Im not a precision shooter (yet) but i do believe my skill to be better than the groups i was seeing. Maybe an off day is possible. Most of the shots felt good. Zoning in on that one good group/sd seems to be a start

 

[padom]

Dont crimp....I havent crimped a AR round ever. Your adding too many variables to narrow down your issue.

Shoulder bump .002-.003, drop powder, seat bullet. I bet if you seat to 1.858" base to Ogive you'll be real close to your optimal seating depth. That's my optimal across all my WOA's.

 

[padom]

Dont crimp....I havent crimped a AR round ever. Your adding too many variables to narrow down your issue.

Shoulder bump .002-.003, drop powder, seat bullet. I bet if you seat to 1.858" base to Ogive you'll be real close to your optimal seating depth. That's my optimal across all my WOA's.

Sorry ignore that base to ogive measurement I forgot your using TMK's. That is best for SMK's... TMK's like to be a little longer in my testing.

 

[padom]

^^^ what padom said. People, myself included in the past, will spend half their barrel life doing load development. Be meticulous with brass prep, find a good flat velocity node, tweak seating depth if needs be to get moa or better ( hopefully better) and go shoot matches. I would bet one of your velocity nodes is somewhere around that 23.4-24.2 spread based on the averages the picture provides. Make sure you're not getting pressure signs or very close to pressure signs ( could possibly go over pressure if the temp gets much hotter, get rain in your chamber).

Try this next range trip :

Spend extra time prepping your brass, anneal, consistent shoulder bump, evenly chamfer and trim. If the brass is all mixed lot random brass, sort it by headstamp and volume.

Load 3 rounds each in 1/10 gr increments from 23.4-24.2 gr. You should have 27 rounds. Separate them in to 3 groups. Put up a target with 9 dots in it. Fire one round at each of the 9 targets. Let barrel cool. Repeat using the same dot for the same charge for your next two batches of rounds. Chrono every shot. Record velocities for each ladder. Go back and look for some place in each group where velocity doesn't really change. It's obviously going to change some, but look for the lowest change in the ladder. Hopefully it's a 3/10gr spread. See if there's a correlation in the velocity flat spot between the 3 groups. If so, you found a velocity node. Now look at your target corresponding to that node. You can measure each group, compare, and see if all the targets from that spread fell in to a nice group. If it's tight enough, reload a few 5 Rd groups using the middle charge from that ladder test to verify its good. If the group is massive, use the middle charge of that velocity node and fine tune your seating depth to tighten the group. If you have access to over 100 yards to do the test, even better.

What was your barrel twist again? Not sure if all woa barrels are 1:8 twist. But if you're running a slow twist, like 1:9, or slower, that could or could not have an affect on group as well. All depends. I had a 1:9 twist that would not shoot 69gr bullets but would shoot 72gr fine, then wouldn't shoot 77gr at all. It ran best with lighter bullets in the 52gr range

I have seen too many issues getting in the center of a node using velocity alone as an indicator. Consistent Point of Impacts has never let me and many others down using Dan's OCW method. I cant say the same when selecting your node based off velocity alone....

 

[Warlok813]

^^^ what padom said. People, myself included in the past, will spend half their barrel life doing load development. Be meticulous with brass prep, find a good flat velocity node, tweak seating depth if needs be to get moa or better ( hopefully better) and go shoot matches. I would bet one of your velocity nodes is somewhere around that 23.4-24.2 spread based on the averages the picture provides. Make sure you're not getting pressure signs or very close to pressure signs ( could possibly go over pressure if the temp gets much hotter, get rain in your chamber).

Try this next range trip :

Spend extra time prepping your brass, anneal, consistent shoulder bump, evenly chamfer and trim. If the brass is all mixed lot random brass, sort it by headstamp and volume.

Load 3 rounds each in 1/10 gr increments from 23.4-24.2 gr. You should have 27 rounds. Separate them in to 3 groups. Put up a target with 9 dots in it. Fire one round at each of the 9 targets. Let barrel cool. Repeat using the same dot for the same charge for your next two batches of rounds. Chrono every shot. Record velocities for each ladder. Go back and look for some place in each group where velocity doesn't really change. It's obviously going to change some, but look for the lowest change in the ladder. Hopefully it's a 3/10gr spread. See if there's a correlation in the velocity flat spot between the 3 groups. If so, you found a velocity node. Now look at your target corresponding to that node. You can measure each group, compare, and see if all the targets from that spread fell in to a nice group. If it's tight enough, reload a few 5 Rd groups using the middle charge from that ladder test to verify its good. If the group is massive, use the middle charge of that velocity node and fine tune your seating depth to tighten the group. If you have access to over 100 yards to do the test, even better.

What was your barrel twist again? Not sure if all woa barrels are 1:8 twist. But if you're running a slow twist, like 1:9, or slower, that could or could not have an affect on group as well. All depends. I had a 1:9 twist that would not shoot 69gr bullets but would shoot 72gr fine, then wouldn't shoot 77gr at all. It ran best with lighter bullets in the 52gr range

Ahh sorry, my barrel is a 1:7 twist. And ill give it a try. What do you recommend for annealing? I Have heard mixed opinions on process and i dont have a dedicated annealing set up.

 

[padom]

Ahh sorry, my barrel is a 1:7 twist. And ill give it a try. What do you recommend for annealing? I Have heard mixed opinions on process and i dont have a dedicated annealing set up.

Dont worry about annealing right now. Airborne68 sells beautiful 1x, ss cleaned, sized, swag, trimmed and annealed brass here in the PX. All I use in my AR's, beautiful stuff.

 

[Warlok813]

Dont worry about annealing right now. Airborne68 sells beautiful 1x, ss cleaned, sized, swag, trimmed and annealed brass here in the PX. All I use in my AR's, beautiful stuff.

Ahh well the problem is that i have a mountain of brass and just cant justify buying more right now. All seperated by headstamp, cleaned, sized, crimps removed, trimmed and all. Just dont have the annealing part yet

 

[padom]

Ahh well the problem is that i have a mountain of brass and just cant justify buying more right now. All seperated by headstamp, cleaned, sized, crimps removed, trimmed and all. Just dont have the annealing part yet

Dont worry about it. Shoot it. And airborne LC brass is cheap.

 

[Warlok813]

Dont worry about it. Shoot it. And airborne LC brass is cheap.

I was considering getting a salt bath set up for annealing but wasnt sure how much it really mattered.

 

[MarinePMI]

If it's once fired, do as padom says...just load and shoot. Annealing isn't an issue until maybe the third or fourth firing.

 

[Warlok813]

If it's once fired, do as padom says...just load and shoot. Annealing isn't an issue until maybe the third or fourth firing.

These have been fired 5 times now. I have been working one set of brass at a time. Could that be part of my trouble? Weird neck tension and shoulder bump because of work hardened brass? Seems possible.

 

[padom]

At 5 firings I leave that shit lay at the range or load it with plinking 55 FMJ load for short range steel/plinking.

Its not Lapua... shit is cheap. Start out with some new or 1x.

 

[padom]

http://www.snipershide.com/shooting...00-00-a-k-free-shipping.6944457/#post-7810955

1000pcs of ready to load for $100 shipped. Great stuff.