Ok, I had a chance to do some more work with the 7LRM.
Before I get into the nittty gritty I just need to restate that Travis is a genius. This rifle shoots like a laser beam. If I do my part the rifle will put 180 VLD's into a group under a quarter inch with ease.
To work on this concentricity issue I took 30 pieces of brass, left ten of them unturned, turned ten of them down to .015 and the last ten down to .0145.
The .015 gives me about 50% of the neck turned and the .0145 gives me about 90% of the neck turned. I'm unwilling to go much further than this due to brass life concerns.
Loaded them all with the same 70.5gr H1000/180VLD load and shot them for groups. (While its unrelated, I got the best result with the unturned brass. I suspect I'm the limiting factor here because the .0145 groups were the next best.)
Took them home and checked them for concentricity. Out of the chamber the unturned brass gives me the best result, about 1.5 thou eccentric. The two neck turned batches give me about 2 thou eccentricity. (again not sure why this is the case, it seems counter-intuitive to me)
After sizing, I had introduced runout up to the 2.5 to 3 thou range. This leads me to suspect the die itself being the culprit because of the 30 pieces I never was able to get a piece of brass to have less than 2.5 thou TIR.
The only other thing I could see it being at this point is a matter of me oversizing, because the brass comes out of the chamber around .319-.320, gets sized down by the die .309 and then takes the bullet about .311. However it seems to me that random chance would give me at least a single piece of brass in that 0-1 thou runout range were this the case.
As always, I'd appreciate some input and guidance. Unless anyone can think of something else to try I think I'm going to give Whidden a call tomorrow and see what he has to say about getting the die checked and replaced.
Was just out shooting pdogs. End of the town was 450yds away, and you could really tell the difference between shooter and AB on those 300yd+ pdogs. A tenth of a mil off equals a miss. When bouncing back and forth between AB and Shooter, it was clear which one would give you more hits if you just went by the numbers shown and didn't apply your own "correction."
@orkan said in DT Bolt Knobs?:
@martino1 I find the factory knob to be of the correct size, and of the correct location. I've not had a need of an aftermarket knob on the newer chassis. The original tear drop design wasn't nearly as good as the current round knob.
Good enough for me, Thanks
@orkan I have some Barts 68gr flatbase I shoot with a 14 twist. That gun makes little holes. I would be interested to see what they did in that 7.75 twist. so when re-barrel time comes I have some options.
825rnds since last cleaned. I always load up about 10-15 rounds and go test fire them before I dedicate a load session. If there's anything going haywire with the brass or components... or the there's a massive shift in load... I can catch it before expending a ton of time and components.
Two 5-shot groups and two singles. Yup, everything's working great... so it's off to sit in front of the Prometheus for a while. At an average load rate of 10rnds every 2 minutes... this won't take long to dump 34gr of H4350 and cap them off with 105's.
As a general rule you want SAAMI minimum chamber. All brass will be slightly (to grossly) smaller than a minimum chamber when virgin. The less you work your brass, the better it performs. Sometimes you need to set the shoulders back a couple .000s so your bolt closes without losing NPA, I shoot mostly offhand so a slight crush fit Works my brass as little as possible. I’m just killing paper or steel so maximum pressure loads are not often needed. I don’t crimp so I get crazy numbers of reloads from my brass. I’ve been shooting the same 1 case in my 32-40 Ballard for almost 8,000 firings in the last three years.
If i was building another custom rifle it would be with a custom action.I have 2 defiance machine actions and both of them had to go back to defiance to get them working like they should have from the start.When travis built me a rifle with a lone peak fusion ti action, it was good to go from the beginning.I agree with orkan on the lone peak actions.
I got the shipping notice today for the parts that are supposed to assist with partial tension-ing of the tilt, instead of all(locked) or nothing (floppy jalopy).
I know it was mentioned in the Magpul thread, but I didn't want to derail that one any further.
Time, temperature, and pressure often interact. The failure modes associated with each of these factors can easily be reproduced catastrophically. Shooting out a barrel is a fatigue failure.
As the bullet travels down the barrel the pressure curve returns to zero once the bullet exits the barrel. The highest pressure is observed while the vessel (barrel segment) is the smallest. The segment nearest the muzzle sees the least amount of pressure because the vessel (still obstructed by the bullet) at that point has the greatest volume.
If the material selection and barrel geometry are unconstrained in design and tested utilizing finite element analysis (FEA) we may easily double or even quadruple barrel life. Material selection (e.g. maraging steel) and barrel thickness (e.g. 6 inches in diameter at the breach) are important decisions affecting function and cost.
Try spitting without inhaling or using your diaphragm muscles. Accuracy over longer distances requires more pressure.
Guys, be proud that it is your improved marksmanship that actually shoots out a barrel. It is a wear item in our sport.
Thanks again to Greg for challenging us.
@tackyp said in Primal Rights and TS Customs killing some dots:
I thought that was the draw of a custom action, the gunsmith doesn’t have to take the time to check it.
What's out there anymore that a guy doesn't have to give a once over before using? Very few items from even fewer companies. Human error, lack of care and quality control, among other things have me looking everything over nowadays.
Just the other day I picked something up at a store and it fell apart in my hands... guess I'll set that down and grab the one behind it. Doesn't matter if I'm shopping for a bag of fruit, a new hammer or a new gooseneck trailer, everything is getting my eye on it a couple of times.
I'm not even calling out a specific company or thing, it's just the way things seem to be now.
At least with my TS Customs rifles, I've just had to run a patch down that new bore and bang, bang, bang. Likewise with my Tangent Theta optics. Mount, zero, done.
Shameless plug for sure, but I know Orkan and Travis, and both are always making sure things are right.
Body position very much has to do with length of pull.
During each class we have a great many students that end up with a much shorter length of pull due to getting their bodies more straight on with the rifle as opposed to out to the side like a little green army man.
Jewell isn't even in the running. They are too unreliable.
I run Timney (not timmy) 517's in almost everything but I wouldn't hesitate to try out a trigger tech. They've been holding up real well for folks and they shoot nice.
First day of spring and the Foundation stock arrived.
Looking forward to using this thing with the ts custom qa knob & cal atlas bipod!
First impressions are all good being that I didn’t have the opportunity to handle one previously.
(Don’t mind the snipery butthook!)
Sharp. and I'm jelly. Mine should be in soon. Programming and inletting for the flat sided Fuzion was more in depth and required a few more changes than John-Kyle had planned.
So I finally made it out to shoot today. I’ve been traveling for work the last few weeks, and coaching my daughter on the weekends.
I am really happy with the Bravo. As I hoped, recoil management was greatly improved. Having a stock that really fits is huge. I was able to get behind the rifle quickly and comfortably. The pistol grip made hand placement second nature. I didn’t have to think about getting my hand or trigger finger into the right spot.
We stuck to just shooting plates and some rocks at long ranges today. I’m going to get out again soon to try some groups.
Danco silicone grease comes in a small plastic ointment tub with attached lid and is available anywhere plumbing parts are sold for pennies. The one in current use might be 20 years old as a light wipe goes a long way, like Imperial sizing wax.
Any jam what so ever and you restrict the bullet's forward momentum. Basically, as the powder expands in the case, you're leaving the "cap" on longer which results in a much more drastic pressure spike. 30 thousandths jam is a HARD jam. You most often can't jam much harder than that because at some point you'll start shoving the bullet back into the case with the lands.
For instance, when fire forming, I'll often have about 30 thousandths of jam. It's generally not easy to close the bolt.
So ten thousandths jam is definitely going to produce more pressure. Likely not enough to cause major problems, all things being equal. ... but sometimes all things are not equal.
@orkan Can’t absolutely say better, but definitely available at car parts stores in rural Oregon. CLR definitely not. TSA wouldn’t let me fly with liquids, aerosols. So, brake cleaner and synthetic motor oil had to get the job done.
After live fire report...works great! As some may know I have usually run scope, rifle combo as canted rifle, level scope. With this plate and the rest of the adjustability of the XLR stock I can adjust the scope and rifle as level level. The cant and cast off plates allow me to properly shoulder the rifle without inducing cant and position the bore closer to the center of my body. The result is no canted rifle and a much more natural cheek weld.
Here's a pic of the KYL rack at 530yds. Normally these are about 300-400yds. Boy is it challenging in today's wind. I only cleaned it 3 times and I bet I tried at it about 10 times. I could go to 4 hits pretty easy most of the time, but the last one would get missed by a bullet width often. The last one on the rack is about 2.5" in diameter. Awful little out there.
I went at it cold with my 16" .223AI and absolutely smashed it for all shots on one of my 3 times cleaning it.
@dddoo7 Until I have time with it in my own hands, I won't be able to say for sure.
The display sure seems like an upgrade over the kestrel, and also the ability to hook it right up to your computer and swap/backup profiles. I can certainly see some situations where it would be nice to have this thing on your arm.
That condensation ain't just on old scopes. I have to wait for the scope to come up to temp in the summer or the condensation makes it hard to shoot. I'm not surprised at all that it moves the poi...but hadnt tested it myself.
What are your thoughts on using CLR on steel barrels, steel parts including an AR-15 Nickel Boron BCG?
I couldn't say. I have only used it on brakes, suppressors, and barrels. Most of that stuff is either stainless or titanium. I wouldn't let it sit on or in something new unattended for any period of time. Frankly, it's so fast acting that you can scrub with it and then immediately neutralize it if you're unsure.
The 223 AI is all i shoot anymore.You will do good with the 50gr vmax.I run the 50 vmax and have been very happy with it.I am also running the 75gr amax and for the bigger critters it gets the job done.Travis did a great job on that rifle.
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