[DepletedUranium]

And the post whoring begins

Ok, so I've been doing some reading here, mainly referring to the 6.8 Barrel Chart that was so nicely put together and picked out the barrels that suited my needs. This build will mostly be a SHTF rifle/long distance shooting.
So i need a 14.5-16 inch barrel, chrome lined, but would take a SS barrel if i had no other option.
Now by long distance i mean a maximum or 300 yards or less. Now the manufacturers i selected are AR15 Performance and Titan Arms based on my required specs. As I was browsing them i noticed AR15 and Titan sell complete uppers.
So my questions are, 1. following the guidelines of the chart and i won't settle for anything less than a A-B quality barrel where i can order just a plain barrel without the complete upper im willing to sign up for the long haul and wait but i just can't find anyplace that meets my specs, and 2. can someone explain to me the grooves between poly, 4,4gr,5,5r,6, etc.. what makes some better than others, Thank you.
-Dep

 

[BLACK LION]

"As I was browsing them i noticed that Titan Arms are going out of business and both AR15 and Titan sell complete uppers. "

:?: :?: :?: :?: :!: :!: :!: :!:
TITAN ARMORY OUT OF BUSINESS????? HE JUST BEGAN !

The xtreme fits your bill.... I dont hink Tim is going out of business....

 

[DepletedUranium]

"As I was browsing them i noticed that Titan Arms are going out of business and both AR15 and Titan sell complete uppers. "

:?: :?: :?: :?: :!: :!: :!: :!:
TITAN ARMORY OUT OF BUSINESS????? HE JUST BEGAN !

The xtreme fits your bill.... I dont hink Tim is going out of business....

My apologies i meant Cardinal Armory, but as i stated before any chance of getting just the barrel and not the complete upper?

 

[paulosantos]

IMHO, the grooves are not as big of a deal as the Chamber. Now, when you combine everything, they all add up and will make a difference in pressure.

So if you have a 1:11"/6-Groove/SPCII Chamber and a 1:11"/4-Groove/SPCII Chamber, the difference in pressure really aren't tha much, but if you have a 1:10"/6-Groove/SPCII and a 1:12"/3-Groove/SPCII Chamber, then you will have a great decrease in pressure. Remember, the 1:10"/6-Groove/SPCII is the MINIMUM specs for a "C" rating. Anything better than that is just gravy.

 

[Jamesb74]

AR performance and Titan sell A-class uppers complete for competitive prices they have the specs you want.

 

[Eliminator]

...any chance of getting just the barrel and not the complete upper?

Titan Armory offers a barrel only option on their e-store.

 

[ron169]

Also, Titan and AR15performance also sell just the barrels. Were you asking what was meant by grooves, as in definition. Or just wondering about the correlation between number or type of grooves and pressure?

 

[LKirchoff68]

Bison Armory also has an order of 16" barrels coming in in a few months. I know that they are not CL, but SS makes for some pretty accurate barrels. Also, Bison is a site sponsor and the owner frequently visits these forums. If you can't get on a list for one of Titan's or ARP's barrels (depending on where you live) it might be a good idea to get on the pre-order list for Bison's 16" barrels.

 

[DepletedUranium]

Also, Titan and AR15performance also sell just the barrels. Were you asking what was meant by grooves, as in definition. Or just wondering about the correlation between number or type of grooves and pressure?

Well in general i guess i was kinda asking both questions, what it is meant by the grooves and what is the correlation between the types of grooves and the pressure

 

[borderpatrol]

Also, Titan and AR15performance also sell just the barrels. Were you asking what was meant by grooves, as in definition. Or just wondering about the correlation between number or type of grooves and pressure?

Well in general i guess i was kinda asking both questions, what it is meant by the grooves and what is the correlation between the types of grooves and the pressure

More grooves or higher grooves (tight bore) increase pressure because more bullet jacket is being squished as the bullet goes through the barrel. This is the easiest explanation I can give. If you only have three grooves being pressed into the bullet you've cut that element of pressure considerably.

 

[constructor]

Edited- To remove the personal attack.
There is a 50 page report at the top of the forum somewhere called the "6.8 performance report" by Tim W.
if you want to take the time to read it, it will explain the benefits of barrel and chamber configurations. You may have to compare some charts and things but the info is there and depending if you reload or not and what kind of performance you desire may or may not be helpful. At the moment it is the most comprehensive test that has been reported to date however,
there are other organizations which have decided the 6.8 is worth investigating further and are about to test the 6.8 in every possible configuration, with every bullet currently made and 3 new bullets being made. In addition to pressure test using a few new powders and other propellants that may be made specifically for the 6.8. There will be terminal performance in gel and performance against armor. The 6.8 project will be an all out effort to obtain the most terminal performance in soft tissue and against armor with new projectiles and powders made specifically to obtain the best results while keeping the pressures within the safe operating range of a combat firearm so there may be more creditable information later this year.
Or you can just look at the chart that some of the guys on the forum put together to make it easy to decide which barrels have better features. I think it is a fair chart that everyone collectively agreed upon, if not I am sure they will change it soon.

Everyone has an opinion and this is a free country to express those opinions, I was wrong to post the message to Paulo on an open forum. sorry Paul

 

[paulosantos]

IMHO, the grooves are not as big of a deal as the Chamber. Now, when you combine everything, they all add up and will make a difference in pressure.

So if you have a 1:11"/6-Groove/SPCII Chamber and a 1:11"/4-Groove/SPCII Chamber, the difference in pressure really aren't tha much, but if you have a 1:10"/6-Groove/SPCII and a 1:12"/3-Groove/SPCII Chamber, then you will have a great decrease in pressure. Remember, the 1:10"/6-Groove/SPCII is the MINIMUM specs for a "C" rating. Anything better than that is just gravy.

There is a complete 50 some odd page report that Tim wrote with all the proof but your opinion contradicts that even though you have done no testing of your own. So we spent 4 years trying to talk manufactures into building the correct configuration and now we are going backwards because you have a 1-10 twist?

OK, so what part did I get wrong? I spoke with Tim on numerous accassions about it and that is the way he explained it. Each one of the three things (Twist/Chamber/grooves), will only slightly reduce the pressure, but if you combine all three together, which is what you guys did with your barresl, you get a huge drop in pressure. Is that not correct and isn't that what I wrote?

Example: With my barrel, which was a 1:10" twsit/6-groove/SAAMI Chamber. Once I converted it to the SPCII Chamber, that dropped the pressure some. If I was somehow able to change the twist to 1:11", that would also drop the pressure some more, and if I was to somehow change the grooves on it, that would also drop the pressure. Am I not correct?

 

[constructor]

My DMR chamber is only .030 longer than the SAAMI and .020 shorter than the SPCII, it shoots everything fine as long as it is in a 11, 12 or 13 twist barrel and there are no bad chrome problems. I had a WOA 11 twist with a SAAMI chamber that would also shoot combat loads.
It just my opinion that the bad angle at the end of the case was an issue with the Extreme bullets. The SAAMI chamber was an issue with the 115 Hornady and Extreme bullets because they were loaded out and touched the lands, that raised pressure enough to cause problems.
There are 10 twist barrels with SPC II chambers on the market that still cause swipes with combat ammo, we saw that at the first test at Chris's and again with Marine's barrel.
Both the twist and chambers do make a difference as does the rifling design and bore area.
I have tested 10 twist 6 groove SAAMI, 10 Twist 6 groove SPCII, 11 twist 4, 5 and 6 groove, SAAMI, SPCII and DMR. 12 and 13 twist 3 groove DMR and 11.25 twist Lothar polygonal DMR chambered barrels.
The 12 and 13 twist 3 groove and the Lothar 11.25 twist polygonal will allow me to load at least .5 gr more than the Xtreme barrels which have very thin width lands. The 12 and 13 twist 3 groove and the poly will allow me to load at least a grain more than any other barrel I have tested which has been every barrel that has come through the shop. Stag, LMT, WOA, Noveske, Kotonics, DPMS, Model 1 and a Douglas 10 twist custom. That is why I paid particular attention to the bore area when designing the Xtreme and 12 twist 3 groove rifling buttons.
Paulo your opinion is the chamber makes the biggest difference, My opinion is it may if the bullets are jammed into the lands
but the bore area IMO is what makes the biggest difference. Less chrome that takes up area on every surface, less lands as in not as wide or number of or just barrels with bad specs.
IMO Twist does effect pressure but does not have as much influence on pressure as it does velocity but the 13 twist 3 groove and the 11.25 twist Lothar poly shows more velocity consistently with the same loads with bullets up to 110gr.
The Barnes and GS Custom bullets with drive bands reduce pressure in every barrel but when loaded to the maximum allowable pressure the 12,13 and 11.25 twist Lothar polys still allow a stiffer charge and give more velocity.
I cannot stuff enough Reloader 7 or 10X powder in the case to see any signs of pressure.

So if we go by the KISS principle you can shoot a 110gr Vmax from a 16" model 1 safely at apx 2450fps which will give 1000ft lbs(what most consider adequate to take big game) of energy all the way to 200yds.
Or we can shoot the correct configuration barrel/chamber with handloads at 2750fps safely and extend that 1000ft lbs to 350 yds. It is no doubt up to the purchaser but lets don't dumb it down to help them make a bad choice, put the numbers out there so they can really see the difference. The Vmax has the best BC and shows the best range, that is the only reason I used that as an example. I would not use the Vmax to take deer.
Now some people will go strictly by the load data from powder companies and never load past the max OAL. That will severly limit performance, most manuals show out to the right what pressure that load developed in their 10 twist SAAMI chambered test barrel and the pressures are still like 48000 psi. Not much performance there.
edited-because I think faster than I type.

 

[paulosantos]

My DMR chamber is only .030 longer than the SAAMI and .020 shorter than the SPCII, it shoots everything fine as long as it is in a 11, 12 or 13 twist barrel and there are no bad chrome problems. I had a WOA 11 twist with a SAAMI chamber that would also shoot combat loads.
It just my opinion that the bad angle at the end of the case was an issue with the Extreme bullets. The SAAMI chamber was an issue with the 115 Hornady and Extreme bullets because they were loaded out and touched the lands, that raised pressure enough to cause problems.
There are 10 twist barrels with SPC II chambers on the market that still cause swipes with combat ammo, we saw that at the first test at Chris's and again with Marine's barrel.
Both the twist and chambers do make a difference as does the rifling design and bore area.
I have tested 10 twist 6 groove SAAMI, 10 Twist 6 groove SPCII, 11 twist 4, 5 and 6 groove, SAAMI, SPCII and DMR. 12 and 13 twist 3 groove DMR and 11.25 twist Lothar polygonal DMR chambered barrels.
The 12 and 13 twist 3 groove and the Lothar 11.25 twist polygonal will allow me to load at least .5 gr more than the Xtreme barrels which have very thin width lands. The 12 and 13 twist 3 groove and the poly will allow me to load at least a grain more than any other barrel I have tested which has been every barrel that has come through the shop. Stag, LMT, WOA, Noveske, Kotonics, DPMS, Model 1 and a Douglas 10 twist custom. That is why I paid particular attention to the bore area when designing the Xtreme and 12 twist 3 groove rifling buttons.
Paulo your opinion is the chamber makes the biggest difference, My opinion is it may if the bullets are jammed into the lands
but the bore area IMO is what makes the biggest difference. Less chrome that takes up area on every surface, less lands as in not as wide or number of or just barrels with bad specs.
IMO Twist does not have as much influence on pressure as it does velocity but the 13 twist 3 groove and the 11.25 twist Lothar poly shows more velocity consistently with the same loads with bullets up to 110gr.
The Barnes and GS Custom bullets with drive bands reduce pressure in every barrel but when loaded to the maximum allowable pressure the 12,13 and 11.25 twist Lothar polys still allow a stiffer charge and give more velocity.
I cannot stuff enough powder in the case to see any signs of pressure.

So if we go by the KISS principle you can shoot a 110gr Vmax from a 16" model 1 safely at apx 2450fps which will give 1000ft lbs(what most consider adequate to take big game) of energy all the way to 200yds.
Or we can shoot the correct configuration barrel/chamber with handloads at 2750fps safely and extend that 1000ft lbs to 350 yds. It is no doubt up to the purchaser but lets don't dumb it down to help them make a bad choice, put the numbers out there so they can really see the difference. The Vmax has the best BC and shows the best range, that is the only reason I used that as an example. I would not use the Vmax to take deer.
Now some people will go strictly by the load data from powder companies and never load past the max OAL. That will severly limit performance, most manuals show out to the right what pressure that load developed in their 10 twist SAAMI chambered test barrel and the pressures are still like 48000 psi. Not much performance there.

I still fail to realize how what you wrote is any different than what I wrote. I totally agree with you. I don't know what else to tell you.

I just think that we have a different method of delivery. I tell guys, here are the facts, pick what you want. Whereas you and Tim are saying here are the facts. Why in the fuck would you want to settle for anything but the best. Am I correct?