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mustangfreek
5 March 2016, 20:18
Finally got motivated and got the 300 bo together, first time playing with this cartridge and am curious on how my brass Looks and leads to buffer question

16" BHW Carbine gas 300 barrel just plan on supers for now, anyways took a quick drive and wanted to test it out, fired a few different factory loads and used a lancer and Troy mag without issues, locked the bolt back everytime.

Upon looking the brass seems dented pretty good on the necks, everyone , I reload and understand the 556 cases get this from the shell deflector.

It is hitting the deflector, maybe to hard? Only had a carbine buffer on me and normal carbine spring,

Is this normal per say for the shorter cartridge? Or overgasssd some and should bring s H buffer to try next?

Anyways some quick pics

http://i194.photobucket.com/albums/z176/mustang91_2007/Mobile%20Uploads/84647785-DC0E-4D49-836D-5026B07E4AFF_zpsf6a2vd7r.jpg (http://s194.photobucket.com/user/mustang91_2007/media/Mobile%20Uploads/84647785-DC0E-4D49-836D-5026B07E4AFF_zpsf6a2vd7r.jpg.html)

http://i194.photobucket.com/albums/z176/mustang91_2007/Mobile%20Uploads/AA839E52-7EE2-4483-B949-BE53BB38780D_zpssvmdivzp.jpg (http://s194.photobucket.com/user/mustang91_2007/media/Mobile%20Uploads/AA839E52-7EE2-4483-B949-BE53BB38780D_zpssvmdivzp.jpg.html)

http://i194.photobucket.com/albums/z176/mustang91_2007/Mobile%20Uploads/72251399-62B0-4F5C-A23F-8F890108BE55_zpsqqj7ozk6.jpg (http://s194.photobucket.com/user/mustang91_2007/media/Mobile%20Uploads/72251399-62B0-4F5C-A23F-8F890108BE55_zpsqqj7ozk6.jpg.html)


http://i194.photobucket.com/albums/z176/mustang91_2007/Mobile%20Uploads/A4BD128E-1020-49AC-9C44-8B9A68C5ABCA_zpsuaobem7q.jpg (http://s194.photobucket.com/user/mustang91_2007/media/Mobile%20Uploads/A4BD128E-1020-49AC-9C44-8B9A68C5ABCA_zpsuaobem7q.jpg.html)

Any input? Something or just shoot it?

Dstrbdmedic167
5 March 2016, 20:23
Normal from what I've seen as the shorter brass is able to complete a full turn and hits the deflecter "better" causing more mouth deformity. As long as brass is ejecting probably just shoot it.


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mustangfreek
5 March 2016, 20:30
Normal from what I've seen as the shorter brass is able to complete a full turn and hits the deflecter "better" causing more mouth deformity. As long as brass is ejecting probably just shoot it.


Sent from my iPhone using Tapatalk

Thanks bud, just my first dip into the BO.
Totally makes sense as the shorter case, all rounds ejected in a good pile about 7-10 foot to the 3-4 o'clock

bzdog
5 March 2016, 20:31
This is normal for 300 BLK. FWIW, my Noveske gen 2 factory rifle came with pistol gas, H2 buffer and also dents the mouth.

-john


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Dstrbdmedic167
5 March 2016, 20:32
When I had my 300 all my brass was deformed more than my 556. My 277 is in between the two. As much as UW may hate it I still like it.


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SwissyJim
5 March 2016, 21:03
Sweet! You get 'er running - awesome. Mine gets dinged too, but one thing I found on my buddy's 300BLK is that his was more dinged than my brass (we were both using the same supers) as his system was slightly overgassed. I tuned mine with the adj block, but he did not have one. We tried the next buffer and it improved some. His brass ejected more grouped and not as forward and the dings lessened. I'd say if you have another buffer, give it a whirl - it can't hurt. The worst that will happen is it won't run as good and you go back. if you don't already have a buffer... run with it, it's not that bad. The dinged brass is one of the reasons I anneal.

EDIT: just read your other post where it's ejecting normal 3-4 position... looks like you're about as normal as you can be. Considering... [BD]

Deadwing
5 March 2016, 21:53
I think you're good to go. My 300BLK brass, subs and supers, looks just like that out of both a Noveske 10.5" upper and a BCM 9" upper using an H2 buffer.

Now you need to get a can![BD]

mustangfreek
6 March 2016, 04:00
This is normal for 300 BLK. FWIW, my Noveske gen 2 factory rifle came with pistol gas, H2 buffer and also dents the mouth.
Sent from my iPad using Tapatalk

H2 huh, assuming shorter barrel


When I had my 300 all my brass was deformed more than my 556. My 277 is in between the two. As much as UW may hate it I still like it.
Sent from my iPhone using Tapatalk

Haha...I have one part from mdws -277 dude/ picked up one of them NIB 158 bolts and running it in this gun.


I think you're good to go. My 300BLK brass, subs and supers, looks just like that out of both a Noveske 10.5" upper and a BCM 9" upper using an H2 buffer.

Now you need to get a can![BD]

Thanks for the reply, I pretty much felt it was normal ish given the shorter cartridge etc, but was just curious, I have no one with a blackout so nothing to compare to- real world.

Yes I do need-want a can, things have just not went my way the last year or 2 and plans changed, did pick up a few guns for hosts and the bo idea was originally for a short barrel-pistol or 2 stamper-SBR


But I wouldn't be opposed to a "go fund me" the wevo ginger a can page...[BD].....anyways..thanks guys..

mustangfreek
6 March 2016, 04:06
Sweet! You get 'er running - awesome. Mine gets dinged too, but one thing I found on my buddy's 300BLK is that his was more dinged than my brass (we were both using the same supers) as his system was slightly overgassed. I tuned mine with the adj block, but he did not have one. We tried the next buffer and it improved some. His brass ejected more grouped and not as forward and the dings lessened. I'd say if you have another buffer, give it a whirl - it can't hurt. The worst that will happen is it won't run as good and you go back. if you don't already have a buffer... run with it, it's not that bad. The dinged brass is one of the reasons I anneal.

EDIT: just read your other post where it's ejecting normal 3-4 position... looks like you're about as normal as you can be. Considering... [BD]

Haha... yes finally running , only forever later huh...BABC had a color change though it turned black and receivers turned silver....[:D]

I will steal a H buffer from a different gun and bring it up next time and see if any change and if it still locks back etc...thanks Jim...wevo ginger normal ...[BD][pop]

bzdog
6 March 2016, 06:28
H2 huh, assuming shorter barrel


No, 16". AFAIK, Noveske used the same recipe for 16" and shorter.

-john


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OTShooter
6 March 2016, 09:07
You're good to go.

Since the Blackout case is 10mm shorter than a 5.56 case, when the case ejects, it ejects earlier in the carrier's travel. Unless it just dribbles out of the ejection port, it's going to hit the brass deflector on the case mouth, instead of near the shoulder with 5.56 cases.

Joelski
6 March 2016, 14:54
Finally got motivated and got the 300 bo together, first time playing with this cartridge and am curious on how my brass Looks and leads to buffer question

16" BHW Carbine gas 300 barrel just plan on supers for now, anyways took a quick drive and wanted to test it out, fired a few different factory loads and used a lancer and Troy mag without issues, locked the bolt back everytime.

Upon looking the brass seems dented pretty good on the necks, everyone , I reload and understand the 556 cases get this from the shell deflector.

It is hitting the deflector, maybe to hard? Only had a carbine buffer on me and normal carbine spring,

Is this normal per say for the shorter cartridge? Or overgasssd some and should bring s H buffer to try next?

Anyways some quick pics

http://i194.photobucket.com/albums/z176/mustang91_2007/Mobile%20Uploads/84647785-DC0E-4D49-836D-5026B07E4AFF_zpsf6a2vd7r.jpg (http://s194.photobucket.com/user/mustang91_2007/media/Mobile%20Uploads/84647785-DC0E-4D49-836D-5026B07E4AFF_zpsf6a2vd7r.jpg.html)

http://i194.photobucket.com/albums/z176/mustang91_2007/Mobile%20Uploads/AA839E52-7EE2-4483-B949-BE53BB38780D_zpssvmdivzp.jpg (http://s194.photobucket.com/user/mustang91_2007/media/Mobile%20Uploads/AA839E52-7EE2-4483-B949-BE53BB38780D_zpssvmdivzp.jpg.html)

http://i194.photobucket.com/albums/z176/mustang91_2007/Mobile%20Uploads/72251399-62B0-4F5C-A23F-8F890108BE55_zpsqqj7ozk6.jpg (http://s194.photobucket.com/user/mustang91_2007/media/Mobile%20Uploads/72251399-62B0-4F5C-A23F-8F890108BE55_zpsqqj7ozk6.jpg.html)


http://i194.photobucket.com/albums/z176/mustang91_2007/Mobile%20Uploads/A4BD128E-1020-49AC-9C44-8B9A68C5ABCA_zpsuaobem7q.jpg (http://s194.photobucket.com/user/mustang91_2007/media/Mobile%20Uploads/A4BD128E-1020-49AC-9C44-8B9A68C5ABCA_zpsuaobem7q.jpg.html)

Any input? Something or just shoot it?

I don't think it's a problem, although I'm not seeing that with my .300 BLK SBR. The thing is, everything should be pretty much equal, given the pistol gas system on both rifles. You're obviously getting more velocity at the muzzle for your 4.5" of extra barrel over my rifle, which increases "Dwell Time" or the amount of gas available to push the bolt back in it's channel. Blackout is reputedly tolerant of all manner of size and velocity of ammunition and barrel length is said to cause a neligible change in gas pressure due to the consistency of the gas system. You could always try your bolt in a .223/5.56 rifle to see if you are getting the same results in order to narrow it down to an ejection event that's causing this. I highly doubt the flat spots are from the casing barely making it out of the way in time, narrowly avoiding a stove-pipe, but it could be possible. Below are some casings from my rifle, taken from 4 different outings. The ammunition is 147 gr Freedom Ammunition of new manufacture. The casings are obviously annealed as well; something I've found more common on 5.56 than .223 ammo. So there are a couple fo differences, but still nothing I'd consider powerful enough to affect ejection. I'd maybe color around the ejection port and on the inside of the receiver near the port with a sharpie (or some black, dissovable paint, nail polish, whatever) if you are really interested in finding out where the strike occurs; paint on the casings would correspond to scuff marks in or on the ejection port.

147 gr SS, 300 BLK:
http://i997.photobucket.com/albums/af93/Joelski144/ARs%20and%20Pistols/MK%2018/20160306_172842-1.jpg~original

Well, hell... I guess I'm the odd man out.

din
6 March 2016, 17:38
Totally normal with 300 BLK brass. If it bothers you put a little piece of adhesive backed loop-side velcro on the shell deflector.

rob_s
7 March 2016, 02:31
I shot thousands of rounds of 300blk, suppressed and non,many almost every case was dented like that.

mustangfreek
7 March 2016, 02:43
Joelski- thanks for the info, I'm all good just was somethin new, as I said first BO rifle,
I'm using a std whatever-whoever carbine spring and carbine buffer, no extra heavy's to try but gonna borrow a H out of a different and see for shits and giggles any difference and if it still operates, functions fine and locks bolt etc..

Also carbine gas barrel and std gas block


No, 16". AFAIK, Noveske used the same recipe for 16" and shorter.

Sent from my iPad using Tapatalk

Huh, interesting , thanks


You're good to go.

Since the Blackout case is 10mm shorter than a 5.56 case, when the case ejects, it ejects earlier in the carrier's travel. Unless it just dribbles out of the ejection port, it's going to hit the brass deflector on the case mouth, instead of near the shoulder with 5.56 cases.

Thanks


Totally normal with 300 BLK brass. If it bothers you put a little piece of adhesive backed loop-side velcro on the shell deflector.

Googling around found people doing the same as concerns of making the Necks weaker and more vulnerable to splitting especially if not annealing..(which I want to touch on in another thread for the bo)

usmcvet
16 March 2016, 06:51
Yeah mine does the same thing too. I thought it was strange but chocked it up to the difference in the neck of the case. My buddy who reloads was all freaked out. I did not care because the gun ran well.

SINNER
16 March 2016, 07:18
Every .300 BO I own does this. As mentioned it's due to the case length. The spent case ejects earlier in the BCG's cycle and has time to rotate before it strikes the shell deflector. I built a slick side .300 I wound up giving to a friend because 75% of the cases bounced off my cheek(I'm a lefty). I have slick sided uppers on 7-8 rifles of various calibers and have never had that issue with any other ones. The annealed cases actually come out looking worse due to the softened brass.

Joelski
16 March 2016, 08:12
Hmmm, then why aren't mine doing the same thing?

Curious.

usmcvet
16 March 2016, 08:33
Hmmm, then why aren't mine doing the same thing?

Curious.

Do you have a shell deflector?

Joelski
16 March 2016, 10:31
Yep.

mustangfreek
31 March 2016, 02:54
Was back out tearing up some other loads, looking them over as usual, dented to crap on some and not much on others.. went home cleaned up a little and looked harder, I mean some of them the lip is bent to shit..

Most of these cases were FC marked converted brass , the factory S&b seemed to be the least dented..

Part 2, didn't put anything on the deflector, but thinking I should? Try a heavier buffer , has a carbine in in it now, maybe a H, or H2 like said above, which I don't have on hand for testing..

Shoots brass at about 3-4 o'clock 5/6 foot , depending

H110 reloads
http://i194.photobucket.com/albums/z176/mustang91_2007/Mobile%20Uploads/2015-02/BB877666-FA24-42E5-9D41-F53F7585DA7F_zpsxwabljhc.jpg (http://s194.photobucket.com/user/mustang91_2007/media/Mobile%20Uploads/2015-02/BB877666-FA24-42E5-9D41-F53F7585DA7F_zpsxwabljhc.jpg.html)

110gr testers
http://i194.photobucket.com/albums/z176/mustang91_2007/Mobile%20Uploads/2015-02/51862EDF-7764-4BB4-B430-F112CF18923B_zpse01ieone.jpg (http://s194.photobucket.com/user/mustang91_2007/media/Mobile%20Uploads/2015-02/51862EDF-7764-4BB4-B430-F112CF18923B_zpse01ieone.jpg.html)

Factory S&B 124gr fmj
http://i194.photobucket.com/albums/z176/mustang91_2007/Mobile%20Uploads/2015-02/785A4A3E-0355-4A88-B854-912157AEED6E_zpscwj9zi1z.jpg (http://s194.photobucket.com/user/mustang91_2007/media/Mobile%20Uploads/2015-02/785A4A3E-0355-4A88-B854-912157AEED6E_zpscwj9zi1z.jpg.html)

I guess I'll bring out a H buffer next time, but I'm a little iffy using done of them tweaked/ twisted neck cases..

Joelski
5 April 2016, 09:48
This is after 360 rounds saturday. The AXTS BCG must have a strong ejector spring?

http://i997.photobucket.com/albums/af93/Joelski144/ARs%20and%20Pistols/MK%2018/20160404_213153.jpg (http://s997.photobucket.com/user/Joelski144/media/ARs%20and%20Pistols/MK%2018/20160404_213153.jpg.html)

bzdog
5 April 2016, 20:57
Joelski, is yours missing the deflector all together? Mine (with pistol gas/h2) showed the brass marks right away:

http://uploads.tapatalk-cdn.com/20160406/a7782c433f2bc91ac9e0783b977ab51a.jpg


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mustangfreek
6 April 2016, 02:01
Same ? Joelski missing it completely or are you covering it with something?

Mine looks like bzdog

Joelski
6 April 2016, 03:30
I don't cover the deflector. Those casings aren't even looking at the deflector on their way out. Puzzling.

DUX
7 April 2016, 14:48
If your rifle is timed and balanced and you have a 4 coil spring, black stand-off, and rubber o-ring or delta-ring in your extractor, the brass won't hit the deflector. As the extractor spring ages it will, minimally. The brass will all pile up at about your 4 O'CLock about 5-6 feet away in a neat little pile. Having a rifle that balances just under the chamber--right behind the magwell--and properly timed (I heard one guy here call it tuned and that's fine too) is critical to having the platform function like that in my experience. Joelski's picture doesn't lie. All my AR's do the same thing.

mustangfreek
7 April 2016, 19:14
Kinda not sure on that comment about balanced and timed has to do with this, tried different spring/ insert in extractor and no difference, have yet to try a h buffer to see..mine land at about 4 o clock but after hitting the deflector..

DUX
7 April 2016, 19:23
Kinda not sure on that comment about balanced and timed has to do with this, tried different spring/ insert in extractor and no difference, have yet to try a h buffer to see..mine land at about 4 o clock but after hitting the deflector..

The balance and timing keep the rifle more stable while firing. If one side is heavier than the other you get a rocking boat effect. Your extractor spring may be older. That's my stab at it.

Deadwing
7 April 2016, 19:37
I don't cover the deflector. Those casings aren't even looking at the deflector on their way out. Puzzling.

I've got 5.56 guns that eject like that and miss the shell deflector completely. Others, ejected cases beat the deflector like it owes them money.



If your rifle is timed and balanced and you have a 4 coil spring, black stand-off, and rubber o-ring or delta-ring in your extractor, the brass won't hit the deflector.

A strong extractor spring, insert, and o-ring will certainly aid in getting the case out of the chamber, but probably don't do much for ejection.

Brahmzy
7 April 2016, 19:38
My 300BLK does the same thing. Uber dents just like pictured.

Joelski
8 April 2016, 03:55
I put in the stuff that the armorer recommends and it works. Springs and buffers aren't hard to understand, but as long as it magically just works, I'll play along. :)

mustangfreek
9 April 2016, 01:30
I put in the stuff that the armorer recommends and it works. Springs and buffers aren't hard to understand, but as long as it magically just works, I'll play along. :)


^^ Okay I'll play along...

Curious what setup buffer/ spring ?
Suppressed ?

Joelski
9 April 2016, 05:41
Standard carbine.
Not suppressed, presently. What game do you think I'm playing?

mustangfreek
9 April 2016, 23:25
Lol...game?


I was just curious what you were running to get it running like that / timed and balanced..

Thought you were on to something about a certain spring/ buffer combo that you were running or something..

Carry on..