223 semi-precision reloading frustration.

[DIYguy]

I have several precision bolt guns that I've manage to work up very accurate loads. Combination of QuickLoad, lots of Labradar strings and spreadsheet data analyses and worked up loads that pretty consistently yield 1/2" groups at 100Y. I also have a custom AR build as a semi-precision gun that I can't get to group. Really nice upper/lower/stock/trigger build with a JP Super Match 18" barrel and thermal dissipator. Had the barrel installation work done by the JP gunsmith, about $750 total. Get groups typically in the 1-1/2" +/- range. The gun SHOULD be good, can't get a consistent load. My other rifles are Lapua brass, Sierra bullets and Redding competition dies and getting SD's in the 4 to 9 range. Pretty happy with those. The 223 is the only setup using Honady Match dies, Hornady brass and Hornady 75g BTHP bullets. Brass prep includes bevel and chamfer necks, pocket prep. Using AR-Comp powder I'm getting SDs typically in the mid 20's up to the 40's. AR-Comp is NOT temperature stable if if they say it is. I finding velocity drop at higher temps, increase at lower temps. IE: 22.6g at 60 degrees = 2630fps, 22.6g at 40 degrees = 2755fps. 108% fill so 8% compress load with 100% burn.
I think the Hornady Match dies are giving very inconsistent neck tension and the AR-Comp is not giving consistent results. The only other powder I have that might work in 223 with 75g bullets is Varget. To achieve similar velocity QuickLoads shows 111% capacity with 93% powder burn. To slow of a burn.
I'm attaching one of the typical analysis/target sheets I typically do and the last page of the seven page spreadsheet of chrono data.
Frustrated.

 

[TxWelder35]

May have to try a different powder. I’ve had good luck with aa2520, cfe233 and 8208xbr

Using the cheapo rcbs dies, unsorted LC/frontier brass, 77smk, and throwing any of the above powders with a Forster powder thrower I’m at around .75” @ 100 without trying super hard. Proof barrel.

 

[Steel head]

8208 is your friend

 

[huntnh]

So is Lapua brass and varget

 

[CK1.0]

IMO the most important variable to sort out is seating depth, and from what you posted, doesn't look like you experimented at all. I don't buy any of that OCW/node crap and all my guns shoot, even my semi-auto's.

Just pick a speed/charge weight, load up a small batch where they're all as exactly the same as the next as you can (most people's real life SD), find a jump range ~0.020-0.040" wide and you'll never have to touch it again.

Also, if you're like a lot of us, I bet your gasser weighs about 15lbs less than your bolt gun and has trigger that's a lot heavier... throw a gamechanger or some other bag with some heft over the top of the scope/whole rig to weigh the sucker down without touching the barrel when you shoot your groups.

 

[Evintos]

Have you tried having another shooter test the load?

Vortex Diamondback Tactical optic in good shape?

Pretty sure the JP Supermatch is a .223 Wylde chamber, so your COAL looks short to me at 2.245" (also means a fairly large amount of bullet jump which could be excessively large). I'd recommend starting at 2.260" or 2.258" (mag length or mag length minus 0.002")

Lastly, what does your load development target look like. The velocity data (for the powder load development) means nothing without corresponding results on target.

 

[davsco]

i have a jp ctr02 (223 wylde) with a 1-6x that i use in 2 & 3 gun. just started reloading from scratch a year ago. 24.0g of varget with ass't range brass and i'm easily sub moa at 100 yds with 69 smk (i realize you're doing 75 so maybe varget isn't the best choice). redding small base sizer die (no neck/bushing stuff) and rcbs matchmaster seater. i didn't play around with seating depth, just copied the black hills blue box that i was replacing (because they stopped making it). jp has a page on their website in which they discuss reloading for their various guns, suggested powders etc.

https://jprifles.com/document_pdfs/JP%20Loading%20Document_757.pdf

edit --coal 2.250

 

[TxWelder35]

Try seating out further also

These mags let you have one of the longest COALs @ 2.300 internal dimensions

ASC AR-15 .223 / 5.56 20-Round Stainless Steel Magazine

The ASC® AR-15® .223/5.56 20-Round Stainless Steel Magazine is a performance-enhanced centerfire rifle magazine, favored by sport and tactical shooters across North America. This lightweight magazine features durable 410 stainless steel constru

gunmagwarehouse.com

 

[DIYguy]

I'll try and address the responses....
I've only run across powder available to purchase once in the last 18 months. Been having to rely on stock in my own cabinets during that time. Have about 8# +/- of AR-Comp and similar for Varget. I use H335 for my 55g bulk loads on the Dillon.

Have LOTS of Hornady 223 brass. My 308 and 6.5cm's are all Lapua. Use Redding competition dies for my three other rifles, S with bushing, Lyman M dies to true the necks, anneal all my rifle brass after every use. I'm pretty sure neck tension in the 223 is an issue. Forster single stage press and sensitive to any variation is seating pressure when seating the bullet. Have notice some seat easier than others.

Regarding seating depth, I have tried from 2.245 to feed failure at 2.268. Attached the last page of 7 pages of test results, there are 6 more pages of charge weights, seating depths, etc. Also helps track velocity shift by temperature. I do have the measurements for distance to lands and use DoL (Distance off Lands) for the other rifles, found max mag length negates this with the 223.

Regarding other shooter. Yes, my shooting mentor is former military with sniper experience. He's mentoring me for PRS competition. Had him try the rifle with reloads and Hornady Match ammo. Same results I get.

davsco: Thanks for the link. As an FYI... I sometime shoot with JP (John Paul) we shoot USPSA together and sometime squad together.

"Lastly, what does your load development target look like. The velocity data (for the powder load development) means nothing without corresponding results on target"
With the original post I included one of my load development pages which includes my target. This lets me compare the actual per shot velocities and compare POI on target for reference. I set up target boards and have a clipboard with me at my bench to log data for each target while testing. Attaching target sample photos.

 

[Desert_Racer]

8208 is nothing more than extruded dogshit. Don’t buy any. I’ll do the community a favor and clear the shelves of it to make more room for other powders you want.

 

[DIYguy]

FYI, about the Labradar reports with target attached. I built an Excel template that takes the Labradar CSV file and maps the data in to fields in my form to make the data easier to read. I build a template for each gun so all the gun data stays the same and inserts the chrono results. I scan the targets as a JPG and insert into my form so I can track load vrs results in a single page.

 

[Evintos]

Do you have the target pics for the loads from 21.8gr to 23.4gr. I'm was looking at your reloading recipes page 7 pdf (there's only one page) and the highest charge weight you tested the 2.250" COAL is 22.4gr and the one random one at 23.4gr.

Your sample of the series data only shows 1 page of a 2.245" at 23.2gr

What's your powder development targets look like?

All I see is data for what essentially looks like powder charge development at 0.2gr increments but with 21.8gr to 22.4gr at 2.250" COAL but for some reason you went down to 2.246" for the powder charge development for 22.4gr to 23.4gr with one random 23.4gr back at the 2.250" COAL but somehow has a CBTO of 1.859". It doesn't seem like you have selected a powder charge to load consistently to nor do I see a constant in COAL.

*(While it's possible to have a 2.250 COAL with 1.859" CBTO match a 2.246" COAL with the same CBTO, it does however either mean erroneous data or it could also mean the bullet base to ogive consistency in this lot is crap and your COAL and CBTO will be inconsistent. Noting that if you compare the powder charges for the COAL at 2.250" with a CBTO of 1.860" to the powder charges at a 2.245" COAL with a 1.859" CBTO. There's a 0.004" difference in COAL that exhibits only 0.001" variation for the CBTO. It'll be hard to make crap bullets shoot well. Crap being relative, there are certainly more consistent bullets out there.)*

What the series of data should've look like for powder charge development was 21.8gr to 23.4gr in 0.2gr increments ALL at 2.250" COAL (although it looks like you're aiming for 1.859" to 1.860" CBTO but why was this CBTO was chosen rather than say 1.865" or 1.870" CBTO). Combine that with the target pics side by side similar to the photo you posted but with powder charge data. Following that, pick the powder charge you wish to load to consistently or that exhibits consistent POI on target, then run test all at that powder charge with seating depth test from mag length down.

So, hypothetically 23gr exhibits same consist POI at say 6 o'clock. You load rounds only at 23gr (+/- 0.01gr, depending on powder measurer resolution) and then run a seating depth test from 2.260" COAL (or the CBTO that corresponds to max mag length) in 0.010", 0.005" or 0.003" increments, with pics of all the targets. Having 1 page of results with one charge weight with one COAL/CBTO and one target is pointless without having something to compare it to.

Basically this pic you posted below - but with all the powder charges listed at a consistent COAL. Then the same pic but with a consistent powder charge.

 

[DIYguy]

Do you have the target pics for the loads from 21.8gr to 23.4gr.

See attached

 

[DIYguy]

Your sample of the series data only shows 1 page of a 2.245" at 23.2gr

Used the one page as a sample but for those that want to dig deeper, here's the rest of the pages

 

[Evintos]

Can you also upload the target pics for the JP barrel for 21.8gr to 22.8gr. Oct 2019 set and Feb 2021 set.

 

[DIYguy]

Regarding variations in COAL and matching CBTO, when I do a batch I'll load 20 to 30 rounds. At the end of the batch I'll randomly pick about five cartridges to measure. If there is a variation I'll pick an average of the measurements for that batch. Also guilty of cut and paste some time when in a hurry and have missed editing one number while editing another. I'm mainly paying attention to load, velocity, temp variations, SD and target results.
I'm highly suspicious that my bad SD results are because of neck tension using the Hornady dies. I think the combination of weak neck tension and compressed loads may be resulting in a few thousands variation in seating depth. With AR-Comp even at 2.255 COAL anything over 21.0g starts a compressed load.
I am curious to see what difference I get to work up some loads with Lapua brass as that's what I use for my bolt guns but haven't found any 223 Lapua in stock.

 

[DIYguy]

Can you also upload the target pics for the JP barrel for 21.8gr to 22.8gr.

Here's a few to play with

 

[DIYguy]

And some more to play with...

 

[Molon]

There are some really stupid replies posted in this thread.




Reloading For The AR-15: Hornady 75 Grain BTHP

Hornady produces three different versions of their 75 grain open-tip-match bullet in 22 caliber (0.224”). For this article, we’ll be looking at the projectile that is colloquially referred to as the “T1”.

The T1 is available as a reloading component, with a product number of #2279 for the 100 count boxes. It’s also available in 600 and 4000 count boxes.

I use the Hornady 75 grain BTHP bullet to load match-grade hand-loads for my semi-automatic AR-15s chambered in 5.56mm/223 Remington. According to Ballistic Performance of Rifle Bullets by Bryan Litz, the Hornady 75 grain BTHP has an average G1 ballistic coefficient of 0.356 and an average G7 ballistic coefficient of 0.183.

The lot of T1 projectiles used for this article have a nominal length of 0.988” and I load them to a nominal COAL of 2.245”. When fired from a Colt SOCOM barrel with a 5.56mm NATO chamber, this COAL will create a jump to the lands of 178 thousandths of an inch. When fired from a Larue Stealth barrel with a 223 Wylde chamber, this COAL will create a jump to the lands of 115 thousandths of an inch and when fired from a Krieger barrel with a 223 Remington chamber, this COAL will create a jump to the lands of 78 thousandths of an inch.

The jump to the lands figures stated above where obtained using a Sinclair bullet seating depth gauge and a Forster 223 Remington 1.4636” head-space gauge. These figures are contingent upon a variety of variables, such as the particular chamber reamer that was used for your barrel, the number of rounds that have been fired through your barrel when the measurement is obtained, the particular lot of bullets used and whether you use a virgin case, a fired case, a resized case or a head-space gauge to obtain this measurement.

WARNING!
Reloading is an inherently dangerous activity. The information provided here is for educational purposes only. It is not intended to be used for the actual loading of ammunition by the reader. No warranty, guarantee or assurance that these loads are safe is stated, suggested or implied nor should any be inferred. Usage of this information for the actual loading of ammunition may result in malfunctions, damage and destruction of property and grave injury or death to beings human in nature or otherwise. Don't even view this information in the presence of children or small animals.




For this hand-load of the Hornady 75 grain BTHP bullet, I use virgin Lake City brass that has been weight-sorted, match-prepped and neck-sized. The cases are primed with Federal GM205M primers and charged with VihtaVuori N140 powder and as mentioned above, the T1 projectile is seated to a COAL of 2.245”. This process is conducted in a semi-progressive manner on a Dillon XL-650 press using a Pact Digital electronic powder dispenser and scale to dispense a powder charge of 24.1 grains of the VihtaVuori N140.

When chronographed from a 20” Colt A2 barrel, a 10-shot string of this hand-load fired over an Oehler 35P produced a muzzle velocity of 2638 FPS with a standard deviation of 4 FPS and a coefficient of variation of 0.15%. (The muzzle velocity was calculated from the instrumental velocity using Oehler Ballistic Explorer.) A 10-shot group fired from one of my Krieger barreled AR-15s, at distance of 100 yards using my bench-rest set-up, had an extreme spread of 0.526 MOA.

....

 

[Evintos]

Regarding variations in COAL and matching CBTO, when I do a batch I'll load 20 to 30 rounds. At the end of the batch I'll randomly pick about five cartridges to measure. If there is a variation I'll pick an average of the measurements for that batch. Also guilty of cut and paste some time when in a hurry and have missed editing one number while editing another. I'm mainly paying attention to load, velocity, temp variations, SD and target results.
I'm highly suspicious that my bad SD results are because of neck tension using the Hornady dies. I think the combination of weak neck tension and compressed loads may be resulting in a few thousands variation in seating depth. With AR-Comp even at 2.255 COAL anything over 21.0g starts a compressed load.
I am curious to see what difference I get to work up some loads with Lapua brass as that's what I use for my bolt guns but haven't found any 223 Lapua in stock.

Looking at the pdf, when you did a charge weight test (21gr to 22.6gr for 9 different charge weights for 0.2gr increments), the COAL looked inconsistent or data was incomplete. Did none of these group well?



When you kept the COAL consistent (2.246 or 2.250), there were only 4 different charge weights tested.


I grouped your target results pic according to CBTO but there's basically only 2 or 3 charge weights tested on those pics with what looks like a randomly chosen COAL/CBTO. Not sure if the targets were part of a seating depth test.

#6 and #7 shows what your barrel could potentially do (tight groups if you discount the fliers), but those charge weights might not be the best choice.

I think you should start your load development again by finding a good powder charge while keeping the COAL consistent. Then mess with seating depth after you narrowed down the best powder charge weight.

 

[DIYguy]

Evintos: Love it!!!! A man after my own heart! If going to be serious about reloading for accuracy have to get serious about the numbers and love the math!
Have to admit you are catching me in some less than perfect data when going back a couple years. I did go back and compare my reload batch cards, range records and spread sheet and corrected some of my COAL and CBTO numbers. I'm going to cop the excuse of getting lazy occasionally while working full time as a project engineer, running my own company and still trying to spend time at the range. Now you're making me feel guilty for less than perfect data. Nuff excesses.
Big gap in load development and testing for the 223. Started playing with load development back in 2019 after the JP upgrade, ran a bunch of test and was never all to happy with results. Added a competition 308 MDT bolt gun to the collection and went spiraling down the rabbit hole for perfecting loads for that gun and the 223 got lonely in the safe. Added another MDT in 6.5cm, perfected loads for that one. Got bored, built a custom 300 AAC blackout this fall, perfected subsonic 220g loads suppressed and remembered the 223 all lonely in the safe.
Every other gun has it's own set of dies and their all Redding Competitions, S dies, bushings, etc. The JP 223 is the only one still running Hornady dies. All the Redding die setups are yielding SD's in the single digit numbers, the Hornady....nope.
After all this discussion I did talk myself into finding some Lapua in 223 and Sierra 77g BTHP bullets, have on order. Shopping online for the Redding Competition dies for the 223, still looking.

 

[Codiekfx400]

You are trying way to hard imo. Change the bullet to a 50 or 55 vmax and try some accurate 2230 or accurate 2200 or ramshot Xterminator powder. If that doesn’t work it might just be the rifle.

 

[three horsemen]

I have several precision bolt guns that I've manage to work up very accurate loads. Combination of QuickLoad, lots of Labradar strings and spreadsheet data analyses and worked up loads that pretty consistently yield 1/2" groups at 100Y. I also have a custom AR build as a semi-precision gun that I can't get to group. Really nice upper/lower/stock/trigger build with a JP Super Match 18" barrel and thermal dissipator. Had the barrel installation work done by the JP gunsmith, about $750 total. Get groups typically in the 1-1/2" +/- range. The gun SHOULD be good, can't get a consistent load. My other rifles are Lapua brass, Sierra bullets and Redding competition dies and getting SD's in the 4 to 9 range. Pretty happy with those. The 223 is the only setup using Honady Match dies, Hornady brass and Hornady 75g BTHP bullets. Brass prep includes bevel and chamfer necks, pocket prep. Using AR-Comp powder I'm getting SDs typically in the mid 20's up to the 40's. AR-Comp is NOT temperature stable if if they say it is. I finding velocity drop at higher temps, increase at lower temps. IE: 22.6g at 60 degrees = 2630fps, 22.6g at 40 degrees = 2755fps. 108% fill so 8% compress load with 100% burn.
I think the Hornady Match dies are giving very inconsistent neck tension and the AR-Comp is not giving consistent results. The only other powder I have that might work in 223 with 75g bullets is Varget. To achieve similar velocity QuickLoads shows 111% capacity with 93% powder burn. To slow of a burn.
I'm attaching one of the typical analysis/target sheets I typically do and the last page of the seven page spreadsheet of chrono data.
Frustrated.

I didn't get 1/2 moa groups with those bullet or any long bullets until I went with a Redding competition seater die with a sleeve. To much run out is not a good thing. I use 4064 and 4166 powder because that's all I have. Been using my last bit of 4320 powder for the Sierra 69 gr MK bullets. Both of my AR's shoot good with these powders. I do use a RCBS ChargeMaster to throw my powder. I would check how much run out you have first.

 

[DIYguy]

Regarding the Redding competition die, I've been thinking the same thing for some time. The Hornady Match die I've been using for these 223 is one of the first dies sets when I started loading for rifle. That's been about five years or so ago. Since then I've switch so every die set is Redding Competition.
The Hornady seating die has a floating sleeve that does not have any tension on it. It just floats up and down. To adjust the die an empty case is set in the press and the die is screwed down until it just makes contact with the cases. This seems like the die is not capturing the full case as the die is still very high up in the press and the sleeve moves up about 1/2" during the seating process.

With the Redding the sleeve has a spring putting tension on the sleeve. The die is adjusted by bringing the ram up and screwing the die down to make contact with the ram. This completely captures the brass. I just went out and took a couple pictures for comparison.

I've been able to get great results and single digit SDs with the Redding Comp seating dies in my other calibers so I just now ordered The Redding set for the 223. I still have 200 to 300 Hornady brass preped and primed ready to load so I'll try loading some test round with the Redding and prep another batch with the Redding S die and see if results improve.

 

[RegionRat]

Has the gun/bbl in question ever shot a tight grouping with any other load?

For example, if you feed it a magazine length standard 77 OTM or TMK load, will/has this rig ever shot a good group?

I only ask because there are two distinct possibilities with your situation (with what little we know from this distance).
One is you have not developed the load or your loading process to conclusion, and/or, two is that this particular bbl may not shoot this bullet well ever.

I will suggest you take a crack at finding something like a 77 SMK match load ammo (Black Hills, Fed, IMI, etc.) to try. With shortages these days that may be a tall order, but then getting a Pet Load together is an option.

It is just my opinion, but a good premium quality AR bbl in the neighborhood of 7 to 8 twist, should produce a fat 1 MOA 10 shot group with a 77 SMK at mag length with something close to a load equivalent of 24 grains of RE-15. There are too many Service Rifle examples to deny what is considered typical performance for a 20" AR with good parts. (And 18" isn't an excuse to have things fall apart.)

Have you consulted with JP about your issue? Would they have you test without the radiator? Take a hard look at an inspection by JP?

If you try a know "Pet Load" for accuracy and you still see this very poor performance, I would suggest you may want to cut your losses. It happens even to the best, just not very often. YMMV

 

[Rant Durden]

I have to 2nd the idea of getting some factory ammo in different weights just to get a baseline.
My heavy barrel AR shoots IMI 77’s very well and the 69’s go into a very small hole.
My reloading for that rig is exclusively lead free Barnes Varmint Grenades (we’ve gotta save the friggen condors here in komiefornia).
No need to load for matches.

 

[DIYguy]

Good points RegionRat. So far I've tried:

Hornady Black @75g
Hornady Match @75g
Hornady High Performance @ 75g
Federal Gold SMK @77g

Best I was achieving was as you said "a fat 1MOA". Have not contacted JP yet or Kevin, (gun smith for JP) wanted to exhaust everything else.
Valid point regarding the radiator. That thought has crossed my mine also. Keven had to mill the heat dissipator down in size slightly to clear the hand guard. JP handguards are pretty large and round and I think they usually intend for the radiators to be used with their hand guards.

 

[DIYguy]

Slightly off topic but as discussing load development and groups thought I would toss another AR build in. Last month I built another new toy, 300 Blackout with suppressor. Was working up some subsonic loads and testing suppressed. Since not a long range rifle was working at 50 yards. Ten ++ round each, subsonic, Strike Eagle @ 4x @ 50y. Better groups than the long range gun. My SD's were all between 4 & 6 using the Redding dies and loading on the Dillon.

 

[nn8734]

Slightly off topic but as discussing load development and groups thought I would toss another AR build in. Last month I built another new toy, 300 Blackout with suppressor. Was working up some subsonic loads and testing suppressed. Since not a long range rifle was working at 50 yards. Ten round each, subsonic, Strike Eagle @ 4x @ 50y. Better groups than the long range gun. My SD's were all between 4 & 6 using the Redding dies and loading on the Dillon.

Apples to oranges insofar as it applies to this rifle though it does indicate you can work up a load.

I agree with the suggestions about trying different ammo. specifically id get my hands on black hills 77g otm 5.56. I wouldn’t bother with .223 Remington ammo as it’s pointless to shoot that low power shit anyway.

I’d be surprised if the BH stuff cant hold 1moa or better. If it does shoot well that means rifle likes the 77g smk, you can prob shave .25 off with hand loads.

 

[CK1.0]

Forgive me if someone has mentioned it already, but, it's an AR, aka Barbie for Men, a bunch of parts cobbled together, and a semi-auto gasser where, when you think about it, its "action" and barrel disassembles and then reassembles itself every time you press the trigger... maybe it's the gun. It's possible your lack of accuracy has nothing to do with your rounds and is just what the sum of its parts are capable of?

Maybe try messing with the buffer system... maybe all it needs is a Blue/Red Springco spring or an H2/H3 buffer weight, etc, or a completely different BCG, different upper, does the trigger suck..? (you get the idea)

If it were me I'd go from cheap/simple to PITA/expensive, and don't rule out your barrel just because it's a JP, while unlikely, I've seen a couple JP rifles that JP made right, but that weren't right straight from the factory.

One of the best AR's I've ever shot was a buddy's Frankenstein made up of (IIRC) KAC, Geisslele, PSA, Radical, Spike's, and probably borderline airsofter shit and it shot 1moa with shitty M193...

 

[kyzim311]

I might have missed it, but I think your combo of brass and dies is not helping your groups. Based on your description, you are running a bushing die. Hornady brass is decent but not great. The neck wall thickness varies more than you will want for your bushing die. I would go 0.002" smaller on your bushing size then use an expander mandrel that is either 0.222" or 0.221" to set the final diameter. 0.002" of neck tension is normal, but semi autos can benefit from a bit more to keep the bullet from moving when running through the action. You can confirm this is the problem by measuring the neck thickness of your brass, but you need a ball mic to really do that right. The other suggestions above are also good.

 

[DIYguy]

Yup, Barbies for Men. In the old days the grease on the hands was from climbing under the hood and then rattling off to the friends "it's gotta....and a....."

So.... It's gotta.....
PSA upper and lower
M-Loc hand guard
Luth AR rifle stock
Rifle buffer and spring
LaRu trigger
Bravo Raptor CH
JP Super Match barrel and dissippator
JP bolt
PSA moly coated BC (I think)

Half the fun is building, other half is shooting.

 

[DIYguy]

I might have missed it, but I think your combo of brass and dies is not helping your groups. Based on your description, you are running a bushing die. Hornady brass is decent but not great. The neck wall thickness varies more than you will want for your bushing die. I would go 0.002" smaller on your bushing size then use an expander mandrel that is either 0.222" or 0.221" to set the final diameter. 0.002" of neck tension is normal, but semi autos can benefit from a bit more to keep the bullet from moving when running through the action. You can confirm this is the problem by measuring the neck thickness of your brass, but you need a ball mic to really do that right. The other suggestions above are also good.

Yup, good stuff. Current dies don't have the bushing which is why I don't trust my neck tension. I can feel the slight difference when seating the bullets using the Hornady so I know there is a variance in tension. Just now ordered another Redding to replace the current Hornadys.
I've considered the ball mic as it's the only way to get an accurate wall thickness but for the few times I would need it I didn't pop the money. Have .249 for diameter of seated bullet was trying to order .246 for neck bushing as wanted a bit more tension being a gas gun but none to be found, had to settle for .247 which is what I'm seeing for sized brass before loading.

 

[CK1.0]

Yup, Barbies for Men. In the old days the grease on the hands was from climbing under the hood and then rattling off to the friends "it's gotta....and a....."

So.... It's gotta.....
PSA upper and lower
M-Loc hand guard
Luth AR rifle stock
Rifle buffer and spring
LaRu trigger
Bravo Raptor CH
JP Super Match barrel and dissippator
JP bolt
PSA moly coated BC (I think)

Half the fun is building, other half is shooting.

I agree!

Well, if you have access to another BCG, that's an easy one to try? I'd just see what you or any buddies have kicking around to play with.. when I first started shooting AR's I remember swapping uppers with a buddy at the range and right away could see I didn't want to give it back...

I've never tried it in a rifle tube, but I've had good luck short-short-stroking carbines that didn't feel right using quarters and the increased preload seemed to make them more accurate (exactly like short-stroking an AR-9 PCC, just more like $0.50-1.00 instead of $1.00-1.75 with a PCC), that would be about the weirdest thing to try that I can think of, and it's free (well less than a dollar).

 

[Molon]

One of the best AR's I've ever shot was a buddy's Frankenstein made up of (IIRC) KAC, Geisslele, PSA, Radical, Spike's, and probably borderline airsofter shit and it shot 1moa with shitty M193...

And the BS in this thread just keeps getting deeper and deeper.

...

 

[CK1.0]

And the BS in this thread just keeps getting deeper and deeper.

...

Nope, not all the time, but often enough to have me looking at the boxes of Black Hills Mk262 on my bench scratching my head...

 

[DIYguy]

And the BS in this thread just keeps getting deeper and deeper.

...

So here's a novel idea, leave and you don't have to worry about. So far, no one has directed any of the BS at you.

 

[CK1.0]

Before we get derailed, @DIYguy, I've never messed with A2 rifle tubes much, but IIRC there aren't too many options as far as springs and buffer weights, I only mostly see them here and there in traditional/classic M16 builds and Mk12 builds and clone stuff.

My go-to has always been: carbine tube/Blue springco/H2, and then I can usually diagnose from there what I need to do (YMMV), but with carbine/A5 tubes there's all sorts of combo's to try. It might be worth a try playing with a carbine tube or maybe A5 tube and some springs if you can easily, because, you never know...

 

[pmclaine]

AR Comp at 22.1 ran great in my AR/bolt 700 with 77 Nosler CC's/SMKs seconds.

Could have been my goto but I tried 8208XBR.

 

[nn8734]

So here's a novel idea, leave and you don't have to worry about. So far, no one has directed any of the BS at you.

Ignore him

Re the rifle, if you can get your hands on some LC 1x fired brass and AA2520, 25g w/the 77 smk is a solid performer. Your particular opmial charge weight may vary slighty but should shoot 1 MOA or better (does .75-1.0 on avg in my mk12 mod1). As a far as your build parts go, nothing sticks out as problematic; changing spring or messing with the buffer may help.

 

[mheimer_45]

I’m my experience change powder if you can. I’ve tried ar-comp for years in 5 different rifles. Never shoot well until my last Bartlein barrel spun up by Keystone. 22.7 of ar comp with a. 73gr eld absolutely hammers so bad I don’t want to try xbr or varget.

 

[DIYguy]

I'm curious what velocity you guys are loading for that you're getting the best accuracy. Hornady Match yields around 2615 to 2675 depending on temp. Federal Gold with 77g SMK are around 2490 at around 60 degrees. Hornady High Performance are a bit hotter at 2720, same 60 degrees. Factory loads always lean towards conservative. Faster isn't always better, so I've tried loads from 21.0 to 23.9 and velocities from 2410 to 2821. According to QuickLoad, anything over 21.0 starts into a compressed load. The only other power that would work for this setup that I have on the shelf is Varget but that's a slower burn and results in a compressed load with less powder but manual shows it takes more powder for the same velocity as AR-Comp. Until powder starts showing up on shelves again I'm stuck with AR-Comp.

 

[pmclaine]

Loaded some .223 on the S1050 yesterday direct drops from the Dillon measure with the funnel and tube polished by me,

Load WCC brass 2X, Win SRP, 23.2 of 8208XNR, 2.26 OAL

Cold bore plus 4

Fits in a half inch circle

5x5

 

[Choid]

The Dillons drop 8208 beautifully. I only wish it hadn't become unobtanium, even compared to other powders. I am stingy with the pounds I have left.

 

[pmclaine]

The Dillons drop 8208 beautifully. I only wish it hadn't become unobtanium, even compared to other powders. I am stingy with the pounds I have left.

Oh God, this fuckstain again.

I just started dropping from a fresh 8 pounder.

I only have 3000 small rifle primers to load .223 so I'm thinking I will have some powder left over.

Looking forward to try it in .308 and avoid having to pull and trickle loads. I love 4064 but I totally trust drops on 8208 and will allow the powder check to do its job.

 

[cornhusker86]

My rock river NM4 prefers Varget w/ the 75's. LC brass, Rem 7 1/2

 

[DIYguy]

Back to the original subject...
Picked up a set of Redding dies, S full length match die and Competition seating. The only neck bushing I could find anywhere was .247 so thought I would start there.

Now for the math.
A loaded Hornady Match round with 75g BTHP has an OD of .2495
New Hornady brass, unfired has an average wall thickness of .0125
Fired, sized Hornady brass has an average wall thickness of .0122

.0122 + .0122 = .0244 + .224 = .2484. (slightly under factory tolerance.
.0125 + .0125 = .0250 + .224 = .249 (matches factory loads)

.249 - .002 = .247 (the neck bushing I have)

Since these are semi-auto loads I would lean towards a tighter fit and strive more for .003 under so that would be a .246 bushing (still looking) What I'm finding is the neck brass tends to rebound a bit so sized at .247 springs back to almost .248 which is what I ended up with for the batch of brass I just resized. Wondering if I need to drop down to .245 for my neck bushing.

And now to start another debate, Neck sizing only die or Lyman M die to size the necks? For my rifle loads I tend to always bevel and chamfer the necks. Since I'm finding variences in the case necks between the new brass and resized brass and (200) plus cases preped and primed using the Hornady, I'm seriously thinking of adding the Lyman M die for the 223 and running them all again to unify them.

 

[Choid]

If you want to use an expander for rifle, or for anything else, the NOE expander plugs are by far the best. I only use them if I am going to run a crimp die, which I do for semi autos (I know, heresy, but it has worked for me,) so what I do is I get an NOE plug that is .002 under as an expander and .002 over to flare, then I run a Lee FCD to take the flared area down to .001 under the area where the expander/mandrel part of the plug went. Mainly I find that they feed more reliably in semi autos that way, and if I pull a bullet there is never any deformation like you would get with a hard crimp.

 

[jLorenzo]

I have several precision bolt guns that I've manage to work up very accurate loads. Combination of QuickLoad, lots of Labradar strings and spreadsheet data analyses and worked up loads that pretty consistently yield 1/2" groups at 100Y. I also have a custom AR build as a semi-precision gun that I can't get to group. Really nice upper/lower/stock/trigger build with a JP Super Match 18" barrel and thermal dissipator. Had the barrel installation work done by the JP gunsmith, about $750 total. Get groups typically in the 1-1/2" +/- range. The gun SHOULD be good, can't get a consistent load. My other rifles are Lapua brass, Sierra bullets and Redding competition dies and getting SD's in the 4 to 9 range. Pretty happy with those. The 223 is the only setup using Honady Match dies, Hornady brass and Hornady 75g BTHP bullets. Brass prep includes bevel and chamfer necks, pocket prep. Using AR-Comp powder I'm getting SDs typically in the mid 20's up to the 40's. AR-Comp is NOT temperature stable if if they say it is. I finding velocity drop at higher temps, increase at lower temps. IE: 22.6g at 60 degrees = 2630fps, 22.6g at 40 degrees = 2755fps. 108% fill so 8% compress load with 100% burn.
I think the Hornady Match dies are giving very inconsistent neck tension and the AR-Comp is not giving consistent results. The only other powder I have that might work in 223 with 75g bullets is Varget. To achieve similar velocity QuickLoads shows 111% capacity with 93% powder burn. To slow of a burn.
I'm attaching one of the typical analysis/target sheets I typically do and the last page of the seven page spreadsheet of chrono data.
Frustrated.

Honestly I have been messing with the 75gr bthps for awhile, they just don't shoot as well as say the 77 gr sierras. I am going to continue to work with them (mostly seems like a backing up from mag length makes them tighten up a little). Try some Sierras to restore confidence in your barrel.

 

[DIYguy]

Finally received my M-die and .245 bushing after eight days from order time. All the way from Iowa to MN. Set up my Forster to resize and the Hornaday single stage for the M-die. Removed the expanded, lubed up batches of brass and did the resize on one press, throat size on the other. Before going through the process was measuring the brass that had been previously sized with the Hornady dies and primed and getting external measurement of +/- .248 and internal of .223 to .2235. After sizing and expanding a few cases I was finding .221 internal after sizing and .222 after the M expander. (first stage only, no flare). Numbers looked pretty good so did (258) of the existing primed cases. Made it to the ranger yesterday (Wednesday) and tested (40) rounds. Crap, getting the same SD numbers I was before.