6mm predator underway

[stagpanther]

Fresh back from testing the ELD's--everything went pretty well for the most part--most of the groups were at or slightly under MOA--nothing remarkable but I think at least points to better potential.

While the C mags did cycle fine--upon examining two FTF cartridges (I overdrove the primers into the primer pockets) I can see the rounds are still taking a fair amount of damage on the way up from magazine to the chamber--and this is costing me in accuracy, I figure I can gain at least .25 MOA if I can get better feeding. I've got a pair of E-Landers on the way--fingers crossed that they help

Decided that I'm not crazy about the minimalist buttstock; though it may simply be that I've grown overly-accustomed to simple Magpul ones.

[stagpanther]

Tried some 95 SMK's since that's one of the bullets the chamber was optimized for. Although everything is shooting fine in terms of cycling, firing and ejecting--I'm still having problems getting group sizes down and I still believe I'm getting some bullet damage and/or perhaps a touch bullet push back. I may have to give up on magazine feed altogether and try just single feed to see if that makes any difference.

[stagpanther]

Tried some non stick powder for a change--A2230--since I was having problems with keeping consistent seating depths with 4895 and 8028 xbr. It appears to have worked quite well. Also new was Nosler's 90 gr e-tip, which I guess is their version of a mostly copper monolithic bullet.

Ran into problems loading the e-tips right away--despite listing the diameter is .243--it's actually .242 to .2425. This resulted in loose neck tensions in the case neck--increasing my worries about bullet push-back during cycling. Luckily I found a 6mm PPC collet factory crimp die on-line so I just used that to crimp the bullet and it seemed to hold and center them well enough.

These are only seated to a COL of 2.213 (that's all the stubby ogive and allowance would allow without jamming in the throat) and had no problem feeding through the C product magazine.

It starting to fog in and rain, so I hurried the group shots off without much time between shots, and I did my typical "one shot flier" out of each 5 shot group--so even though these are not "honest" groups I think they still point some useful info.

[stagpanther]

Here's my last batch for a while--I need a break from "obsessing" over this one. These are Lapua cases necked down and 95 hunting VLD's seated out to a COL of 2.3. Powder is A2230.

[stagpanther]

Went out this morning and shot the 95VLDs--I continue to have problems with holding the gun steady enough through the entire cycle and so I don't think I can draw any solid conclusions about good loads, even though I still get groups like this.



I'm going to have to sort my technique and set-up out better before I proceed--the costs of load development pile up fast.

[stagpanther]

tried again today after adjusting the stock and scope a bit--didn't seem to make much difference. One thing that is a bit odd is that I can feel the recoil pressure ramp up noticeably with fairly small incremental charge increases. I'm staying well under max pressures and the cases are showing no pressure signs (and hornady grendel cases readily do). I'm going to need to do some research to see how I can bring these group sizes down--I should be able to get well under .5 MOA.

[stagpanther]

Pair each of e-landers and stoner grendel mags came in today. The stoners are simply relabled ASC's--the e-landers look like their white follower is a tad different from the blue ones--don't know if that will help the "lift" any or not. Neither of them will help get the cartridge to chamber if the COL is much beyond SAAMI spec--though the stoner one has more room than the AA/E-lander. My personal biased opinion is that this is a tacit admission by AA that you simply can't bullets seated long without smacking the meplat into the breech face due to the lack of shoulder lift from the case. The bullets go in and the rifle fires--but there is still taking some deformation and that's costing in accuracy--not to mention the risk of spiking pressure if it hits too hard with a stout load of powder.

My bag of tricks is just about empty. I thought about lightly adding some extra radius to the barrel extension's chamber opening--but I figure the odds are good that will cause sealing/erosion problems over time. Makes me wonder why nobody has bothered developing an improved extension design with ramps that get the cartridge into the chamber in better style??

[stagpanther]

Went out this morning for one last go with the hunting VLDs after messing with all the new magazines. As my luck would have it--soon after getting set up it started raining and blowing pretty good--and instead of calling it a day I rushed the groups, starting to get frustrated with this project after sinking about $500 into loading materials and a smorgasbord of magazines. Here's one of the better ones--seems like A 2230 is the best powder I've found so far. Still don't know if this is the best load cause all the other groups did fairly well except for a flier which was just as likely because of me pulling the shot.



Ironically, the best performing magazine was my old C products mag that I modded years ago for a grendel build--all the fancy (and expensive) new stuff in the end offered no advantage in consistency or accuracy. Funny how that works out sometimes.

[stagpanther]

Waiting on parts to start a 458 socom build--so back to the 6mm predator for fine tuning. : )



Put a ctr buttstock on (again) and also took off the muzzle brake and put a JP tanker on. I'm not finding that the recoil is excessive, but I'm looking for a way to possibly see if I can reduce the amount of movement when shooting--it's not a heavy recoil, but a "snappy" one if that makes any sense.

I finally got everything configured to reliably cycle and chamber standard berger hunting VLD's--not an easy thing to do in an AR platform because of their ogives.

[stagpanther]

Here are some new 95gr tipped matchkings driven by 8028 xbr. Most of the groups were similar to this with the occasional flier--OK--almost always a flier.





I still can't seem to keep the weapon steady all the way through the trigger pull, no matter what I do I get a bit of roll off the bags before the bullet has exited the muzzle--I know the reason the groups aren't tighter is because of me pulling the shots. The rifle itself is purring like a kitten.

I was wondering about just how powerful this 6mm in a grendel case is--here is the berm backstop behind by target box.



My conclusion--the 6mm predator is a "reloader's delight" at this point--you're going to spend time tuning your rifle to work reliably and then it's going to take a while to find the "eureka load"

I still wonder why nobody has come out with an improved rifle ramp extension for the grendel-based cartridge--I've messed around with the cartridge enough over the years to realize how it's accuracy and reliability are limited in part by simply getting the cartridge into the chamber in good condition. Worse yet, it can be prone to bullet set-back if the set-up results in the bullet meplat smacking the chamber face on the way in--and with the right (wrong) powder that can easily result in pressure spikes. Just my hobbiest opinions--I'm sure someone can prove me totally wrong.

[stagpanther]

I'm sure you guys are bored to death by now with my 6mm predator posts--frankly I am too. LOL

Today went out in the 90+ degree heat (very unusual for coastal Maine) and slapped a bipod on my 6mm predator to see if that makes any difference. I actually did shoot a little better--which is hard to figure since I almost always get better results shooting off of bags. What is becoming clear is that the slightest movement of any kind is going to throw the shot. i know duh.

What is clear to me is that the 6mm predator is an inherently accurate cartridge--even in an AR. No matter what bullet or charge weight I used--the bullet almost always lands within MOA of point of aim at 100 yds--a different parameter from measuring a grouping at under MOA--but maybe just as important--perhaps more so in applications like hunting where you might only get 1 shot. I shot 95gr tipped matchkings and 108 ELDs and needed only a click or two adjustment to the scope's elevation and windage settings to cover all the different cartridges and charge weights to the next.

In the groupings below, they were all 4 shot groups (running out of bullets) and wherever you see 4 impact holes but only 3 shots counted in the group--that's because I choked and pulled on that shot. I still managed to get a couple of decent 4 shot groups--but you can see that in the 3 shot groups if I hadn't pulled the flier it still would be hard to figure out which charge weight would be best. When I get "problems" figuring that out--it's because I'm still not shooting up to par with what the rifle can do.

Harrison at AR15 Performance designed the chamber to be able fire certain cartrides (not all) that are seated long (a 95 MK should be able to chamber all the way out to 2.336 or thereabouts) I failed to get any kind of cartridge much longer than 2.27 to repeatedly feed from the magazine without the bullet taking some damage on the way in--a few blown primers and slightly bulged cases reminded me that I was getting some bullet set-backs occassionally, so homey don't do that anymore. With a better extension set-up this should one laser-beam accurate cartridge I think.

[surveyor]

I'm not bored with the posts, I'm rather enjoying them instead.
It is an interesting wildcat, and I know that the entrance to the wildcats den is greased with imperial sizing wax, and is slippery.

Looks great,and is a lot of work.

[stagpanther]

Sometimes I wonder if people know it cost me hundreds of dollars to come up with pictures of those groups (excluding the rifle). LOL

[surveyor]

Well, I have gone through 100 bullets doing load development with 2 powders, and that was before tweaking seating depths, and that was with a non wildcat caliber that did not require fireforming.

I have to shoot about 70 fireform loads before I have enough brass before I can get started seeing what my wildcat really likes with 3 diffrent weight bullets. And diffrent powders,Then I get to do it again for a semi auto, as I'm doing the bolt version first.
And I have load data from a similar cartridge on the same case but a little less capacity to draw from, as well as what others have done with both fresh formed as well as fireformed cases.

I need to shoot about 130 fireform loads to get brass for the ar.

So yes I can appreciate what it takes to show the pictures and chrono velocities, and load ladders.
The progress looks great to me.

[stagpanther]

So yes I can appreciate what it takes to show the pictures and chrono velocities, and load ladders.
The progress looks great to me.

You're too kind. ; )

That's why we keep telling everyone that the real reason to reload is to save money. lol

[stagpanther]

Meanwhile, for your viewing pleasure, here is the next project awaiting completion once the needed parts to complete it are done going round and round in circles somewhere in the middle of the country. Last check the parts have returned to Fedex's depot in TX 3 times!!

[stagpanther]

Decided to take a break from my other projects and get some more work done on my 6mm predator gun. I've often mentioned in other threads that cartridges can take damage on the way into the chamber--even if they successfully feed. Here's an example of what I'm talking about--this is a 95 gr berger VLD--a high secant ogive bullet that because of difficulties with magazines and feed ramps, may glance off of the chamber's face upon feeding--or even possibly wedge in the throat if the throat's angle and taper doesn't accommodate the profile of the bullet.



Using a compact powder could potentially result in a compressed charge in what otherwise would be a safe load; possibly spiking pressures.

Most of my shooting so far with this wildcat has simply been trying to figure what works and what doesn't. I spent a whole lot of money on a large variety of magazines; and as it turns out none of the high end to premium magazines works as well as an ASC with slight modification to the feed lips. This is especially true with high SD/BC bullets with long tapering ogives.

I tried some "secondary ladder" loads of the 95 VLDs with 2230 today--unfortunately I had to leave after only a few groups--too bad, things were getting off to a pretty good start.

[stagpanther]

[FrankenMauser]

Your pics have died.

[stagpanther]

I know--overnight photobucket decided they are going to charge for 3rd party linking. They already make money off of advertising and use of my images--no way I'm paying them additional. Any other hosting service or way to get images up here?

Anyway, here's an attempt through the attachment feature. I just bought these 103 hunting ELD X's and I'm very excited about the potential of these bullets from hornady.

[FrankenMauser]

Sounds about right. I was recently berated by a mob of members for sharing my (very low) opinion of Photobucket on another forum, but the last couple days have turned half of the internet into poster boards of "please log in..."
I may go serve few helpings of crow on that forum.


Attachment no worky.

I usually just resize to 800 pixels maximum on the longest side and upload directly to TFL (and then tweak further if still over the size limit).
For other forums, or projects shared more than one place, I use my own domain (formerly hosted by Yahoo -- now Aabaco Small Business, or something like that). Costs me $100 a year, but I use it for more than just sharing pictures/files.

[stagpanther]

That's odd--did the direct upload--worked for a while--and now is gone?

[CalmerThanYou]

Would have been nice if they grandfathered in prior use photographs rather than littering threads with that annoying notice. All those beautiful pics gone to the ether is a shame.

[stagpanther]

Sorry about that--I guess that's photobucket's way of holding me ransom--I had no idea this was coming until it was a done deal.

[ed308]

I'm done with Photobucket. The ads for the free version have become to much to deal with.