On the edge of insanity!!

[STI_1911_Guy]

Help Wanted!!
So gents here is the story of the 6xc woes. This rifle is a remington 700 remage build/manners t4 adjustable (glass/pillar bedded)/ timney trigger, criterion 26in varmint barrel. This rifle will shoot lights out on new factory norma brass as seen in the sample images (steel was 800yd 3 shot)loaded with either 105 hybrids or 107 sierras and 39.8gr of H4350 fed 210 primers. The problem occurs when i try to reload the brass being it will not group nearly as well(upwards of 1 MOA or more and really bad jumps at distance), and i have done this with about 5 batches of 100 brass now. My brass prep goes as follows:
Vibratory clean
Deprime/size .002 bump forster dies (not sized if i plan to anneal yet) (anneal if needed, i have tried annealing after first firing to no different affect)(bench source)
Ultrasonic clean (usually wait outside in sun for couple hours to dry or overnight inside)
Trim RCBS trimmer (within .001")
Chamfer inside and out using VLD inside chamfer and rcbs outside debur. (these are motorized)
Flash hole chamfer
Primer pocket depth uniformer
Hand prime with RCBS tool ( i actually notice the new 6xc norma brass is the tightest pocket of any brass i have ever reloaded for in my life)
Load using rcbs chargemaster and rcbs press.

My new brass out of box prep goes:
Size all (basically to just round out the mouths)
ultrasonic
quick debur inside and out
primer pocket
prime
load

I cant believe i am hurting these somehow on the second load that i dont on the first but i am open to any ideas right now. I do reload for other calibers and rifles (dpms lr-260/fna3g/various hunting rifles ) and i dont see these issues. One thing i do notice is the bullets seat as smooth as butter on new brass but on my first reload they do take more force to seat. It seems smooth, not like new brass but smooth enough however its just a little harder. Runout is good all under .003 most under .002". seating depth is uniform. The expander ball on my forster die is .2405" and leaves the inside case neck .240". I didnt measure any new norma neck size. Thoughts?

 

[918v]

Fireformed and Virgin cases like a different powder charge. Work up separate loads for each type of case.

 

[zipollini]

I've been fighting this battle of high SD and SD for the past 4 months and this is what finally got me into the low single digit SD and ES. I just followed the bench rest guys lead. If this looks familiar I posted this on another thread.

Equipment - Gun - T2K chambered in 6XC - Norma brass - Lapua Scenar L 105gr and DTAC 115gr BN coated - 39.5 gr H4350 powder - Wolf lg rifle primers

Brass prep for pre fired and prepped brass

1. deprime

2. tumble brass in Thumler's Tumbler with stainless steel media with 1 liter H2O, 1 tsp LemiShine and 1 tsp cream of tarter for 3 hrs - this does a great job on primer pockets - http://www.sinclairintl.com/reloadi...-tumbler-stainless-steel-media-prod42994.aspx

3. separate media and brass and rinse in filtered or distilled H2O

4. dry in oven at 200deg. F for 2 hrs

5. anneal after EACH FIRING with Benchsource annealing machine - http://bench-source.com/id81.html

6. measure neck thickness of each case and sort by .0005 to .001 inch groups - I use the Sinclair neck thickness gauge - http://www.sinclairintl.com/reloadin...prod36959.aspx

7. spray lube cases and inside of case necks with One Shot spray lube - make sure you don't spray inside of case body - just outside of body and inside of necks.

8. full length size with Redding S type FL sizing die and proper size neck bushing to yield .0015 to .002 neck tension - I use a .269 bushing size mostly. I use a RCBS single stage Rock Chucker Supreme press. Nothing fancy.

9. Expand neck using Sinclair expander - http://www.sinclairintl.com/reloadin...prod38807.aspx - Note : if the cases are new and haven't been inside chamfered yet I do that step before I expand the necks. I also sort brass in this step. If I feel the expander inserts into the case either too easily or too hard I pull the case out of the batch.

10. trim brass to length using Sinclair/Wilson trimmer - control length to .001 inch - http://www.sinclairintl.com/reloadin...prod39292.aspx

11. chamfer inside of neck with K & M adjustable chamfer tool - this is really important !! - keeps chamfer depth consistent and thereby neck bearing length - http://www.kmshooting.com/catalog/c...olled-depth-tapered-reamer_large_6mm-338.html

12. chamfer outside of neck with standard tool - I use a Lyman case prep express - http://www.sinclairintl.com/reloadi...se-prep-units/case-prep-xpress-prod42938.aspx

13. uniform primer pocket with standard tool - I use a Lyman case prep express

14. Brush inside of case neck with 6mm bronze barrel brush

14. chamfer, deburr and uniform inside of flash hole with K & M tool - pretty important - http://www.kmshooting.com/catalog/f...ole-uniformer_professional-standard_0080.html

15. wash cases in warm soapy water

16. while washing brush inside of case necks with nylon brush to remove brass chips and case lube

17. while still wet, wet sand outside neck chamfer with 2000 grit sand paper. Make sure you do not thin the neck. Just smooth out any burrs on the outside chamfer

18. final H2O rinse in filtered or distilled H2O.

19. dry in oven at 200 deg. F for 2 hours

Finished brass sorting

1. water weigh each case with 21st Century plugs and separate into groups of .10 grain groups. Heavier cases will generally yeald faster MV while lighter cases will generally yield lower MV. http://www.21stcenturyshooting.com/P...cket_Plugs.php

2. After sorting let air dry

Priming

1. I use Wolf primers that are fairly hard and need to be carefully seated deep and to the same depth every time. I use the 21st Century adjustable primer seater. It's a work of art. Great piece of equipment - http://www.21stcenturyshooting.com/S.S_FQUY.php

Charging

1. Throw charge on a Chargemaster to 1 grain under my final desired weight

2. trickle up to final weight with an Omega II trickler - http://www.omegapowdertrickler.com

3. I use a Sartorius Entris 64-1S analytical balance that weighs to one kernel or .001 grain easily. I switched from a Chargemaster to this scale and my SD and ES were cut in half immediately. Not cheap but worth every penny in time saving and accuracy. - Lab analytical balance Sartorius Entris64-1S

Here is a great video or the scale and the Omega II in action - http://www.youtube.com/watch?v=jr1Wso6P9ZI

Bullet sorting

1. With the DTAC 115 bullets I sort by bullet weight into groups to .10 grain. I use the Sartorius analytical balance for this. Very fast.

2. With the DTACs I also have to sort by bearing surface length using the Sinclair bearing surface gauge - http://www.sinclairintl.com/reloadin...prod38769.aspx

3. With the Lapua Scenar L 105 grain bullets the QC is so incredibly good that I do not have to sort by weight or bearing surface.

Bullet seating

1. I use a Forster competition micrometer seater and seat both the DTACS and the Scenars .040 long and then just close the bolt gently on them to seat them in the lands. This way my seating depth is always the same. For me it yields great accuracy also.

2. I never check for bullet run out as I have checked it many times with my Hornady runnout gauge and it has never been more than .001 inch. I suppose I should probably be checking cases for neck concentricity but have not found it necessary so far. Maybe in the future.

That's about it. A lot of prep time and a lot of expensive equipment.

 

[STI_1911_Guy]

You surely put the work into your brass. I appreciate the advice. The only thing on my end that doesnt make sense to me is the fact they shoot great to start and then the reload gets worse. If brass was an issue i would think i would have an issue to start.

 

[Milo 2.5]

Fireformed and Virgin cases like a different powder charge. Work up separate loads for each type of case.

This guy is right, once you fireform your brass, most likely case capacity changed, so pressures changed, now you just somehow have to get to where you were to started=new brass.

Some rifles make the transition painlessly, others need tweaking.

 

[918v]

It takes energy to expand the case and seal the chamber. A fireformed case does not need to expand. So the energy normally consumed to expand the case is diverted to pushing on the bullet, thereby changing the internal ballistics. If your load is fragile, that difference could throw you out of the node.

 

[Temp9]

In my experience, new/fireformed case capacity doesn't matter all that much in actual practice. 58kpsi has a funny way of expanding brass with little effort. I've used the same loads in new and 12+ times fired brass and get the same POI, same accuracy, same velocity.

To the OP, one thing to remember is that ultrasonic and stainless media tumbling clean the case necks to levels vibratory cannot, so special precaution has to be taken after cleaning with these processes. The absolute bare metal in the brass has an annoying tenancy to gall against the copper in the bullet. This will leave long scores down the length of the bullet's bearing surface. To mitigate this, you need some kind of dry lube (graphite, mica, etc.) in the case neck prior to seating. Of course, then I would assume your first loads would be bad, as well, but it's something to consider for future reloads.

The other thing to check is neck tension. Preferably, you want .0010-.0015" neck tension for bare bullets, maybe a bit more for coated bullets. If you can, ditch the size/expand die and get a good bushing die.

 

[918v]

In my experience, you often need to add powder to the load when using a virgin case to reach the same velocity as in a fireformed case, in factory rifles anyway. This is in low SD loads, where you can actually see a change in velocity.

 

[LBZ]

STI, what Temp9 said about case necks and cleaning is true, Try skipping the ultra - sonic cleaning, don't even brush the necks untill they have been fired twice. Also fireformed brass "can" require a different powder charge.

 

[MitchAlsup]

My guess is that your chamber is a little on the generous side--which dimension I cannot say.
You have found a recipe for the interior volume of the virgin cases, but this charge weight lands on an anti-node after being fire formed.
Thus, you should take the fire formed cases and develop a load specifically for them.
Don't be surprised if it takes 0.3 gr to 0.6 gr more powder to find the accuracy node again.
{Std disclaimer about starting low and working up slowly watching pressure signs.}

 

[STI_1911_Guy]

the only reason i ultrasonic is to remove the hornady one shot after sizing. Would just wiping the one shot off with the rag be ok? Then i wouldnt have a need to ultrasonic which would reduce my need to wait for dry time.

 

[918v]

Super clean necks do not cause a .5" load to shoot 1".

My necks are super clean. I tumble in stainless media. I have no problem with accuracy.

 

[zipollini]

I just wash my cases with warm soapy water and brush the inside of the necks with a nylon brush to remove the One Shot Lube.

 

[STI_1911_Guy]

agreed, but it cant help when bullets slide into virgin cases like butter and reloaded ones grind in.

 

[918v]

But that's not due to US cleaning.

I think maybe your die is causing too much neck tension. What is your sized empty neck vs loaded neck diameter?

 

[STI_1911_Guy]

.267" & .270" respectively. Still the virgin brass go through this sizing die and yet seating is nothing like the once reloaded brass. What could be the difference then?

 

[918v]

Neck hardness.

Reduce the neck tension to .001"

Or anneal after every firing.

 

[STI_1911_Guy]

I have thought about trying the neck tension but i just didnt really want to buy another die but i may go that way. These were annealed this time on my bench source annealer.

 

[918v]

Did you anneal before or after sizing?

 

[STI_1911_Guy]

prior

 

[918v]

What I noticed in my case prep is that annealing forms a rough oxide that makes bullet seating difficult. So I anneal before sizing and let the expander ball smooth out the inside of the neck. But I stainless tumble again for a second time and the pellets polish the inside of the neck. Bullets go in like butter.

You clean with US and that does not smooth out the neck.

I think the only solution is a bushing die and .001" neck tension.

Or ditch the US tank and go with stainless tumbling.

 

[wildfowler]

Zip

Are you using that K&M chamfer tool every time even if you don't trim the case?

Of course when I read the description like what's in the link you posted I feel like that's a new tool I'm going to have to have.

Thanks

 

[kansas]

Lose the die with the expander ball in it and call Lee about making you a collet die.

 

[zipollini]

Zip

Are you using that K&M chamfer tool every time even if you don't trim the case?

Of course when I read the description like what's in the link you posted I feel like that's a new tool I'm going to have to have.

Thanks

I usually don't have to rechamfer if the case doesn't need trimming. If I do have to trim I rechamfer with the tool but it usually doesn't need it unless I have to trim a lot off. It' a great tool. Controls chamfer depth and thereby controls the neck bearing surface length.

 

[SWRichmond]

Neck tension. My vertical at 1k diminished noticeably when I started annealing and using an expander die on all sized cases. Group sizes shrank when I started using a neck bushing die.

You said that seating bullets in fired resized cases was hard. Too much neck tension, and you must solve this. You are shrinking case necks too much. Also, work hardening the necks will make them spring back and be tight.

Tumble
Anneal
tumble again
Fl size with neck bushing that gives .002 tension
Brush necks
Dip necks in powder neck lube
Expand
Clean primer pockets
Trim if necessary

Etc...

 

[AIdog]

Sounds like ur getting out of the node with ur fire formed brass... Compare loads with a cronograph and adjust powder charge. Insanity is doing the same thing over and over expecting different results

 

[steve123]

OP, try some NECO dry lube applied with a Q-tip into the insides of the neck before seating.

 

[STI_1911_Guy]

Quick update. 39.8 is where the charge needs to stay, however the neck being lubed lightly with one shot and q-tip, as this is all i have on hand, helped reduce group size and keep it there. I have about 20-30 rounds left so after that the next reloading should be better with the lessons learned.