Suggestions for a custom barrel maker (<9in)

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Suggestions for a custom barrel maker (<9in) - depletedyourcranium - 03-04-2021

So I'm looking for a custom barrel maker to slice me up a PDW-sized Grendel barrel, somewhere in the 8-9 inch range. You guys have any good suggestions? My preference would be on a fast turn around time, seconded by lower cost. Accuracy is not a requirement for this rig so all those Shaw and Krieger blanks would be wasted. I did find a maker a couple months ago when I was first toying around with the idea in my head that had specced one out for like <$250 with their website menu, but I can't remember and I didn't book mark it.

Suggestions for a custom barrel maker (<9in) - mdram - 03-04-2021

i dont think any custom guy will be fast right now
if accuracy is not a concern, just grab one off the shelf

Suggestions for a custom barrel maker (<9in) - depletedyourcranium - 03-04-2021

mdram Wrote:i dont think any custom guy will be fast right now
if accuracy is not a concern, just grab one off the shelf

I would love to but no one offers a stock barrel in that barrel length range.

Suggestions for a custom barrel maker (<9in) - StoneHendge - 03-04-2021

"Fast" is a relative term. https://columbiariverarms.com/configure-your-custom-barrel/configure-your-264-lbc/

Suggestions for a custom barrel maker (<9in) - James Young - 03-13-2021

I have been looking into this as well. I'm curious how comparative 6.5 Grendel is versus the 300 Blackout in short barrels. So far I only have estimates based on limited data, but my numbers suggest that the short Grendel barrels should be superior to Blackout barrels 3.0" longer. A 7.5" Grendel barrel will equal the energy of a 10.5" 300 Blackout in a similar grain weight (~125) and easily outshoot it at distance. The 7.5" barrel Grendel should also have the same energy as a 77 grain 5.56 out of a 16" barrel but will struggle to keep up at distance.

The same is theoretically true in comparing 6.5 Grendel to 300 Blackout in the popular 5.5" Sig Rattler and less popular 5.5" Maxim PDX. In a 5.5" barrel the Grendel should be ~200FPS faster with ~200-300 ft lbs more energy. The problem is we have no real data at these barrel lengths, and it is not unusual for calibers to lose significant velocity at the shorter lengths.

Suggestions for a custom barrel maker (<9in) - 65GbySeven - 03-17-2021

I've used this guy's for 5.56 barrels. Good shooters easy MOA with factory ammo. Haven't used him for Grendel. Give him a call and ask about turn around time. Looks like less than $200 and you can send him a bolt for head spacing.

https://deadshotbarrels.com/collections/config-barrels/products/ar-15-grendel-caliber

Suggestions for a custom barrel maker (<9in) - depletedyourcranium - 03-26-2021

65GbySeven Wrote:I've used this guy's for 5.56 barrels. Good shooters easy MOA with factory ammo. Haven't used him for Grendel. Give him a call and ask about turn around time. Looks like less than $200 and you can send him a bolt for head spacing.

https://deadshotbarrels.com/collections/config-barrels/products/ar-15-grendel-caliber

Funny you should mention them because that's who I ended up finding and was the one I got the quote from awhile back. Took my dumbass like a week to realize I had got the quote in an email and could just search for it. So ordered March 4 and it shipped March 24... so I'm pretty happy as far as turn around time goes.

Specs were:

8.5 inch length
pistol gas
Unnamed chromemoly barrel blank
1:9 twist
HBAR profile
No muzzle threads but opted for a "magna port" and target crown (was a little cheaper)
Tungsten Cerakote

Worked out to be $200 shipped, so not too bad. I'll get some good pics of it when it arrives (supposed to be here Monday.)

Suggestions for a custom barrel maker (<9in) - depletedyourcranium - 03-26-2021

James Young Wrote:I have been looking into this as well. I'm curious how comparative 6.5 Grendel is versus the 300 Blackout in short barrels. So far I only have estimates based on limited data, but my numbers suggest that the short Grendel barrels should be superior to Blackout barrels 3.0" longer. A 7.5" Grendel barrel will equal the energy of a 10.5" 300 Blackout in a similar grain weight (~125) and easily outshoot it at distance. The 7.5" barrel Grendel should also have the same energy as a 77 grain 5.56 out of a 16" barrel but will struggle to keep up at distance.

The same is theoretically true in comparing 6.5 Grendel to 300 Blackout in the popular 5.5" Sig Rattler and less popular 5.5" Maxim PDX. In a 5.5" barrel the Grendel should be ~200FPS faster with ~200-300 ft lbs more energy. The problem is we have no real data at these barrel lengths, and it is not unusual for calibers to lose significant velocity at the shorter lengths.

When I get it built I'll chronograph a could factory loads out of it and post up my results. I'll have some 12.5's and some 10.5's that I have recently build that I can compare it to so we can kind of maybe get an idea of what that velocity loss looks like the shorter you go. My 8.5 inch barrel is supposed to be "magna-ported" as an option I selected which looks like its two lines of ports about .75 to 1 inch long drilled at about 45° from the top of the barrel... so those velocities may be more representative of what a 7.5 barrel may do over than of a true 8.5 inch. If this build all goes well I may contact him and see if he could make me something ridiculously short like 5-6 incher.

Suggestions for a custom barrel maker (<9in) - 65GbySeven - 03-28-2021

depletedyourcranium Wrote:When I get it built I'll chronograph a could factory loads out of it and post up my results. I'll have some 12.5's and some 10.5's that I have recently build that I can compare it to so we can kind of maybe get an idea of what that velocity loss looks like the shorter you go. My 8.5 inch barrel is supposed to be "magna-ported" as an option I selected which looks like its two lines of ports about .75 to 1 inch long drilled at about 45° from the top of the barrel... so those velocities may be more representative of what a 7.5 barrel may do over than of a true 8.5 inch. If this build all goes well I may contact him and see if he could make me something ridiculously short like 5-6 incher.

Nice! I am very curious to see what velocities you get. I had a 12"PSA for a bit. Shot great and pretty good velocities.

I was going to build a blackout, but I have a bunch of Grendel Brass, so if you can get some decent groups with it... I'll have my next build all planned out.

Suggestions for a custom barrel maker (<9in) - fabbrisd - 03-28-2021

"No muzzle threads" - now that gave me a chuckle - your shorty is going to BOOM... have fun

Suggestions for a custom barrel maker (<9in) - kmon - 03-28-2021

fabbrisd Wrote:"No muzzle threads" - now that gave me a chuckle - your shorty is going to BOOM... have fun

That is what I am thinking, loud blast and flame thrower combined.

Suggestions for a custom barrel maker (<9in) - depletedyourcranium - 03-29-2021

Yeah I've not quite found my way into the suppressor game, so this is going to be a double-up with plugs and muffs time at the range with this gun, and should serve as a secondary way to signal aircraft from the ground with the muzzle flash.

Suggestions for a custom barrel maker (<9in) - depletedyourcranium - 03-30-2021

So my barrel came yesterday. First impressions are that its a little nicer than what I was expecting but still a little rough around the edges. No major concerns, just the barrel extension was a little scuffed and the drilling on the ports, while they look pretty daggone cool, are a little rough. There was some overspray from the cerakote on the crown so I couldn't get a sense of just how well done it was but regardless it looks fine for me and my purpose with this barrel. I'm not trying for or expecting anything beyond 3 or 4 inches at 100 yards with this thing. I will say the barrel as a whole looks pretty fucking cool, pardon my French.

[Image: M34KB3O.jpg]

Markings and gas port. I had actually ordered a 1:9 twist, but only because that's all that was in stock in the standard barrel blank... so if it actually is 1:8 that's great. I'm going to only be shooting factory stuff anyway so I don't think 1:8 or 1:9 would make a spits worth of difference for me.

[Image: Ht5CE8u.jpg]

Shot of the "magnaports". Holes are a little rough and could use a chamfering, but the flutes really make it them look cool.

[Image: C40o1HV.jpg]

Best shot I could get of the recessed crown. Looks a little rough but I think that's mostly from the cerakote.

Suggestions for a custom barrel maker (<9in) - depletedyourcranium - 03-30-2021

[Image: jALlZ91.jpg]

Compared to a 10.5 BCA barrel for scale.

Suggestions for a custom barrel maker (<9in) - StoneHendge - 03-30-2021

Those ports are reminiscent of a P-40 Warhawk. It needs shark teeth!

Suggestions for a custom barrel maker (<9in) - Oso Polaris - 03-31-2021

I don't have a shorty 6.5 Grendel and there is a number of reasons that it doesn't make sense. The 300 Blackout was designed for this purpose. There is only so much powder that can be burned in a given length barrel. The bore diameter can affect this rate (large bore allows for larger flame). The next step is to play with powder selection to find a faster burning powder to offset a shorter barrel length. The fastest powders (burn rate) are pistol powders, which makes sense because you're talking about a 3"-5" barrel for most pistols. The most popular powder for short barreled 300BO is H110 (W296 is same powder), and it is basically a pistol powder. With 300BO you are loading 18.5gr of H110 into case with 125gr bullet. My 8" barrel spits it out at 2050fps and 16" barrel at 2250fps, and I believe that somewhere around 14" barrel the bullet achieves maximum velocity (full powder burn). I think that in the 16" barrel the velocity is actually beginning to slow from barrel drag...I definitely see this in my 18" barrel.

You aren't going to outperform the 300BO with shorty 6.5 Grendel. Assuming use of same powder, the smaller bore diameter of 6.5 Grendel will restrict powder consumption compared to .308 bore size of 300BO. Also, case capacity will work against you with 6.5 Grendel forcing you either downloading to roughly 60% of case capacity or loading normal case capacity and throwing +50% of powder (unburnt) into your suppressor for a secondary detonation or create a giant fireball in front of the gun. Finally, 300BO can operate subsonic and run flawlessly using +190gr bullets while the 6.5 Grendel becomes a single shot.

I think the Grendel starts to shine with 16" barrels and longer.

Suggestions for a custom barrel maker (<9in) - depletedyourcranium - 03-31-2021

I don't care about optimal powder burns and which caliber best utilizes its potential in whatever barrel length. I care about downrange performance. That either begins with your intended range, or your intended barrel size. If you're working within a specific intended target range, you can select your caliber and corresponding barrel length to give you the terminal performance that you need. With most hunting bullets with a minimum expansion velocity of 1600-1800 FPS, that means you can use 6.5 Grendel for hunting medium sized game down to around the 10-12 inch barrel range if your target is <350 yards give or take. Even with a 16 inch barrel, .300 Blk is a 200 yard deer gun, at best.

If you start with barrel length and work forward, you can see if your target range will fall within your intended use or not, which of course, all depends on your muzzle velocity. From what we've seen in super sonic loads, 6.5 Grendel is always matching or beating .300 Blk in the same bullet weights at the same barrel lengths. That just means that the 6.5mm bullets with the better BC's are going to quickly outpace those .30 caliber bullets, giving you better down range performance both ballistically when it comes to wind drift and drop, and terminally when it comes to energy and expansion. So you can say that Grendel will never outperform .300 Blk, but that's just not true unless you put some qualifiers as "in subs/supressed" or "equivalent powder loads".

So if we're just talking about what can they actually do at the muzzle, either with equivalent factory ammo OR whatever handload you got for max velocity, 6.5 Grr will always match or beat .300 Blk, which means that the high BC bullets are just always leaving the 30 cal ones behind... so you'll always get better range and better terminal impacts at the same range when comparing them.

Now don't get me wrong, .300 Blk is an excellent caliber. For suppressed use its phenomenal. It uses more standard .223 AR parts and mags, that's a pain in the ass with building a 6.5 Grr. It handles subsonic loads more easily than other calibers. It's a potent medium game cartridge out to about 150-200 yards. It's probably the most popular AR cartridge next to .223, meaning you've got a wider selection of factory ammo and barrels to choose from. But to say "You aren't going to outperform the 300BO with shorty 6.5 Grendel." that's just not true. Yeah it may make a big fireball but if by performance we actually mean downrange performance... 6.5 Grendel all day.

Suggestions for a custom barrel maker (<9in) - Old Bob - 03-31-2021

StoneHendge Wrote:Those ports are reminiscent of a P-40 Warhawk. It needs shark teeth!

I was thinking Buick Roadmaster... Big Grin

Suggestions for a custom barrel maker (<9in) - Oso Polaris - 04-01-2021

I agree with the better BC of 6.5mm over .308, but honestly out of a sub 10" barrel no one is trying to go any distance. Competitions have proven that flat based bullet are superior out to 300 yards then BTHP. So the BC means a lot less at these shorter ranges. The 300BO has a wider cross-section resulting in better expansion at lower velocities and a bigger hole. Moreover, just from cartridge efficiency you don't/can't consume all the powder in the Grendel case.... more like less then 50% of it, which means you are dumping it into your can or making a large fireball which does not help with night shooting, follow-up shots, and definitely kills any stealth you may have been enjoying. This is why I say 300BO wins in short barrel. Oh Yeah, 30 round magazine fits 30 rounds.

Just because you can doesn't mean you should. Lots of guys shooting 300BO consistently and accurately at 300 yards. Not the way I would go for hunting game... but fine if your killing paper. Its personal taste and perspective.
There is a guy standing behind you nodding his head in agreement with everything you just said, Except that you lost him as soon as he realized that you weren't talking about a real caliber... his 12.5" AR10 (6.5 Creedmoor). The beauty of AR15 is that I can have a 8" 300BO for home defense and handy brush gun for pigs within 150 yards, a 16"-20" Grendel for 600 yards and then something else for longer. If Alexander Arms hadn't put a strangle hold on the 6.5 Grendel when it was introduced I probably would have never picked up the 300BO.

Suggestions for a custom barrel maker (<9in) - biodsl - 04-01-2021

depletedyourcranium Wrote:So my barrel came yesterday.

Slick looking barrel! Let us know how things go.