10yr Review of 17.6” Lilja 6.5 Grendel

[LRRPF52]

I just realized it has been 10 years since I put together the 17.6” Lilja from the first forum group buy. It’s a unique Wasp contour barrel that is really lightweight, but has been repeatedly-accurate and quite precise for such a light AR-15. It has also been boringly-reliable after many range trips, shooting courses, and load-testing sessions over these years.

The main ammo I have fed this carbine is hand loads of 31.2gr of CFE223 under 123gr A-MAXs, as well as Hornady 123gr ELD-M factory ammo.

I basically shot this blaster from 2014-2017 almost exclusively for anything LR until I built the 12” Grendel. I shot some 16”, 22”, 20”, and 18” as well, but really focused on that 17.6 Lilja until I did the 12”, then have mainly focused on the 12”. I usually take them both though. I had been shooting a 16” Grendel prior to this since 2009.

Since last year, I’ve been having my youngest son shoot it to get him trained-up and shooting steel at distance.

He has shot it at 300yds, 400yds, and 1000yds so far with a very high hit rate. I think he only had 1 miss at 1000yds out of 4 or 5 rounds of the new 100gr ELD-VT.

6.5 Grendel 17.6” Lilja

Lilja 17.6” Wasp contour barrel with MLGS, .076” gas port, bedded into the upper
Precision Firearms NOX Flash Hider
Maxim/Precision Firearms Grendel bolt
Standard bolt carrier (later replaced with Bootleg adjustable gas carrier)
M4 with No Forward Assist upper, Cerakote FDE by me
Midwest Industries Free Float handguard with 12 o’clock continuous rail, FDE
BCM Gunfighter Charge Handle

Old School PSA A2 forged lower, Cerakote FDE
Geissele SSA, then LaRue MBT-2S trigger
SPR or Magpul MOE+ grip
VLTOR Clubfoot or LaRue RAT stock
Carbine RET, Cerakote FDE
Carbine spring
Carbine buffer

NightForce Unimount 20 MOA
Vortex Viper PST 2.5-10x32 the whole time, still tracking, dead-on at 100 to 600yds.

Weight without bipod or magazine was 7lbs 12oz initially with the Vltor Gen I Clubfoot. It balances out better with the LaRue RAT stock, but might be slightly heavier. Feels amazing in the hands, like an older M4 with the Wasp 727 barrels pre-SOPMOD heavy pipes.

It has been just a great little lightweight carbine that shoots more like a heavy bolt gun on-target.

Things I would do differently (nit-pics):

I would use an ADM UIC Ambi billet lower receiver or cut a PDQ lever channel into the A2 before I Cerakoted it.
I maybe would have spec’d the gas system to Intermediate Length and had PF do the work on the barrel with their ILGS set-up.
I would have gone with the LaRue RAT stock out of the gate maybe with the bag rider attachment from LaRue.
I would have preferred a handguard with a small 6 o’clock section of rail for a QD bipod option so I could use my TBAC bipod on it more easily.
I would have painted the scope and mount.
Maybe texture the SPR grip and Cerakote it FDE.
I would have Cerakoted the barrel FDE.

 

[Huskydriver]

I just realized it has been 10 years since I put together the 17.6” Lilja from the first forum group buy. It’s a unique Wasp contour barrel that is really lightweight, but has been repeatedly-accurate and quite precise for such a light AR-15. It has also been boringly-reliable after many range trips, shooting courses, and load-testing sessions over these years.

View attachment 8377777

View attachment 8377778

The main ammo I have fed this carbine is hand loads of 31.2gr of CFE223 under 123gr A-MAXs, as well as Hornady 123gr ELD-M factory ammo.

I basically shot this blaster from 2014-2017 almost exclusively for anything LR until I built the 12” Grendel. I shot some 16”, 22”, 20”, and 18” as well, but really focused on that 17.6 Lilja until I did the 12”, then have mainly focused on the 12”. I usually take them both though. I had been shooting a 16” Grendel prior to this since 2009.

Since last year, I’ve been having my youngest son shoot it to get him trained-up and shooting steel at distance.

He has shot it at 300yds, 400yds, and 1000yds so far with a very high hit rate. I think he only had 1 miss at 1000yds out of 4 or 5 rounds of the new 100gr ELD-VT.

6.5 Grendel 17.6” Lilja

Lilja 17.6” Wasp contour barrel with MLGS, .076” gas port, bedded into the upper
Precision Firearms NOX Flash Hider
Maxim/Precision Firearms Grendel bolt
Standard bolt carrier (later replaced with Bootleg adjustable gas carrier)
M4 with No Forward Assist upper, Cerakote FDE by me
Midwest Industries Free Float handguard with 12 o’clock continuous rail, FDE
BCM Gunfighter Charge Handle

Old School PSA A2 forged lower, Cerakote FDE
Geissele SSA, then LaRue MBT-2S trigger
SPR or Magpul MOE+ grip
VLTOR Clubfoot or LaRue RAT stock
Carbine RET, Cerakote FDE
Carbine spring
Carbine buffer

NightForce Unimount 20 MOA
Vortex Viper PST 2.5-10x32 the whole time, still tracking, dead-on at 100 to 600yds.

Weight without bipod or magazine was 7lbs 12oz initially with the Vltor Gen I Clubfoot. It balances out better with the LaRue RAT stock, but might be slightly heavier. Feels amazing in the hands, like an older M4 with the Wasp 727 barrels pre-SOPMOD heavy pipes.

It has been just a great little lightweight carbine that shoots more like a heavy bolt gun on-target.

Things I would do differently (nit-pics):

I would use an ADM UIC Ambi billet lower receiver or cut a PDQ lever channel into the A2 before I Cerakoted it.
I maybe would have spec’d the gas system to Intermediate Length and had PF do the work on the barrel with their ILGS set-up.
I would have gone with the LaRue RAT stock out of the gate maybe with the bag rider attachment from LaRue.
I would have preferred a handguard with a small 6 o’clock section of rail for a QD bipod option so I could use my TBAC bipod on it more easily.
I would have painted the scope and mount.
Maybe texture the SPR grip and Cerakote it FDE.
I would have Cerakoted the barrel FDE.

Wtf is the suppressor lol

 

[Keith E.]

I just realized it has been 10 years since I put together the 17.6” Lilja from the first forum group buy. It’s a unique Wasp contour barrel that is really lightweight, but has been repeatedly-accurate and quite precise for such a light AR-15. It has also been boringly-reliable after many range trips, shooting courses, and load-testing sessions over these years.

View attachment 8377777

View attachment 8377778

The main ammo I have fed this carbine is hand loads of 31.2gr of CFE223 under 123gr A-MAXs, as well as Hornady 123gr ELD-M factory ammo.

I basically shot this blaster from 2014-2017 almost exclusively for anything LR until I built the 12” Grendel. I shot some 16”, 22”, 20”, and 18” as well, but really focused on that 17.6 Lilja until I did the 12”, then have mainly focused on the 12”. I usually take them both though. I had been shooting a 16” Grendel prior to this since 2009.

Since last year, I’ve been having my youngest son shoot it to get him trained-up and shooting steel at distance.

He has shot it at 300yds, 400yds, and 1000yds so far with a very high hit rate. I think he only had 1 miss at 1000yds out of 4 or 5 rounds of the new 100gr ELD-VT.

6.5 Grendel 17.6” Lilja

Lilja 17.6” Wasp contour barrel with MLGS, .076” gas port, bedded into the upper
Precision Firearms NOX Flash Hider
Maxim/Precision Firearms Grendel bolt
Standard bolt carrier (later replaced with Bootleg adjustable gas carrier)
M4 with No Forward Assist upper, Cerakote FDE by me
Midwest Industries Free Float handguard with 12 o’clock continuous rail, FDE
BCM Gunfighter Charge Handle

Old School PSA A2 forged lower, Cerakote FDE
Geissele SSA, then LaRue MBT-2S trigger
SPR or Magpul MOE+ grip
VLTOR Clubfoot or LaRue RAT stock
Carbine RET, Cerakote FDE
Carbine spring
Carbine buffer

NightForce Unimount 20 MOA
Vortex Viper PST 2.5-10x32 the whole time, still tracking, dead-on at 100 to 600yds.

Weight without bipod or magazine was 7lbs 12oz initially with the Vltor Gen I Clubfoot. It balances out better with the LaRue RAT stock, but might be slightly heavier. Feels amazing in the hands, like an older M4 with the Wasp 727 barrels pre-SOPMOD heavy pipes.

It has been just a great little lightweight carbine that shoots more like a heavy bolt gun on-target.

Things I would do differently (nit-pics):

I would use an ADM UIC Ambi billet lower receiver or cut a PDQ lever channel into the A2 before I Cerakoted it.
I maybe would have spec’d the gas system to Intermediate Length and had PF do the work on the barrel with their ILGS set-up.
I would have gone with the LaRue RAT stock out of the gate maybe with the bag rider attachment from LaRue.
I would have preferred a handguard with a small 6 o’clock section of rail for a QD bipod option so I could use my TBAC bipod on it more easily.
I would have painted the scope and mount.
Maybe texture the SPR grip and Cerakote it FDE.
I would have Cerakoted the barrel FDE.

Nice work, thanks. Hella small nitpick list after a decade.

Keith

P.S. I don't need another cartridge. I don't need another cartridge.....

 

[bobke]

LR-Have followed your work, council and guidance for the last 10+ years over on Grendel forum and more recently here, and will give you either credit/blame for a collection of Grendels that I try to keep in active rotation year round. Solid advice, willingly given and well appreciated. Haven’t gone the SBR route yet, though it remains a possibility. Keep those kids shooting-they are the future of the sport.

 

[LRRPF52]

Wtf is the suppressor lol

TBAC Ultra 5 is on my 12” Grendel. I have 8 different Grendels now ranging from 22” down to 8.5”.

I have no plans to put a can on anything MLGS 18”, which is why if I was doing it again I would go with a longer gas system.

For suppressed, 14.5” is about as long as I want to go.

 

[bfoosh006]

Very nice.

Any idea of the round count over those 10 years ? ( just curious )

 

[LRRPF52]

Very nice.

Any idea of the round count over those 10 years ? ( just curious )

I was just trying to figure that out myself. I failed to keep a round count log.

The various load development work alone is substantial though, aside from my go-to volume shooting.

I used it in events and courses at least 6-8 times per year from 2014-2019, not counting any zero confirmation, load development, or campouts. Since 2020, I would say it goes out 2-4 times per year, and picked-up over the last year since I put my kid on it.

I’m guessing 5,000-7,000rds.

I put a lot of Precision Firearms 123gr Scenars and 123gr SMKs through it, as well as 120gr Scenar-Ls that come in the 50rd boxes.

Shot a lot of 123gr A-MAX and 123gr SST until the 123gr ELD-M came out.

When Hornady had the 200rd ammo cans of 123gr American Gunner, I packed my shopping cart full to the point that my little guy got evicted from the child seat, and the bottom rack of the cart was packed too. I miss $139.99/200 days for Hornady. Sportsman’s had a grand opening and Black Friday event with crazy deals that day in 2017.

I don’t have any of that left. Great ammo that has high hit probability at distance.

I’ve also shot a lot of 120gr Federal OTM through it, as well as some 110gr PPU. For my hand-loads, I typically loaded 100-300x 123gr A-MAXs before any course or event.

Even with that round count, it’s shooting like it did out of the gate.

The only reason I’m posting this stuff is for people that are looking to roughly duplicate it for themselves if they want a formula.

I did de-edge, blend, and polish the feed ramps, chamfered the ejector, made sure the extractor didn’t have any sharp corners, bedded the barrel, and bedded the gas block and tube. I used low torque on the muzzle device per suggestions from AMU.

This one has a real SAAMI chamber cut by Bill Alexander. The original chamber was done with another reamer spec that we didn’t bless-off on, so I sent it to Bill and he short-chambered and re-indexed the gas port TDC for me, cut a special gas tube length for it since it’s actually maybe .625” short of a MLGS, hence the 17.6” and not 18”+ barrel it was originally.

 

[LRRPF52]

The first time I was able to group it at 1000yds on a large gong, it did this with 6rds rapid-fired. Reticle was close to 2 mils into the wind off the target, with elevation dialed-in:

5rd and 9rd groups for the 123gr A-MAX/31.2gr CFE223 load at 100yds (before I put a Geissele in it, standard trigger):

 

[DHDeal]

I've read where you've mentioned this barrel/rifle multiple times. I was curious why 17.6" and what was the approximate round count and now I know. Probably the biggest curiosity was what was the gas tube length. I wouldn't have guessed MLGS (-) but I didn't really consider the age of the barrel. Seems we're getting longer all the time on gas system length.

It's good to read that they last a long time.

 

[rlsmith1]

Nice! Why do you grab the 12" so much more?

 

[LRRPF52]

Nice! Why do you grab the 12" so much more?

Not really much ballistic difference between the two, and the 12” is still shorter OAL with a 5” suppressor. I wanted to spend at least 3 years with the 17.6 to get really familiar with how it performed, with some one of the tests being:

* Walk a 12” popper or steel plate/stand out to UKD over 500yds, walk back to firing position in the field, time yourself to 1st-round hit without use of LRF. First time I did this, I think I Mil’d it to 566yds, something like that. Sun had already set by the time I got back, but I could still see enough to break shots, 1st-round connect, followed by another.

* Out of the case, engage steel at 600yds cold-shooter for 1st-round. Just did that 2 weeks ago, impact was within 2” of center-punching it.

You just don’t see much difference through the scope behind 12”, 14.5”, 16”, and 18” Grendels though. I can show you the minutiae with a ballistics program, but it doesn’t mean much to me as a shooter behind the optic and breaking shots. MV with a 123gr is between 2320-2490fps between those 4 barrel lengths with the same load.

The 12” even with a can is very easy to throw into a very small carbine case, toss in the vehicle, and go camping, shooting, and 4-wheeling without taking up much space.

I’ll do a 7yr update on the 12” Grendel as well. It has a duplicate sister in a 2A Balios Lite receiver set/handguard, so it’s interesting to compare the 2 as to how they’ve been doing. Same barrel and BCG in both. I connected 1st-round with the 12” Grendel at 900yds with 110gr PPU that I have not been able to get to shoot under 2.75” at 100yds. Figured it would just make close range fodder, but I went 3/3 at 780yds, then 1st-round at 900yds. Unbelievable...

 

[rlsmith1]

Not really much ballistic difference between the two, and the 12” is still shorter OAL with a 5” suppressor. I wanted to spend at least 3 years with the 17.6 to get really familiar with how it performed, with some one of the tests being:

* Walk a 12” popper or steel plate/stand out to UKD over 500yds, walk back to firing position in the field, time yourself to 1st-round hit without use of LRF. First time I did this, I think I Mil’d it to 566yds, something like that. Sun had already set by the time I got back, but I could still see enough to break shots, 1st-round connect, followed by another.

* Out of the case, engage steel at 600yds cold-shooter for 1st-round. Just did that 2 weeks ago, impact was within 2” of center-punching it.

You just don’t see much difference through the scope behind 12”, 14.5”, 16”, and 18” Grendels though. I can show you the minutiae with a ballistics program, but it doesn’t mean much to me as a shooter behind the optic and breaking shots. MV with a 123gr is between 2320-2490fps between those 4 barrel lengths with the same load.

The 12” even with a can is very easy to throw into a very small carbine case, toss in the vehicle, and go camping, shooting, and 4-wheeling without taking up much space.

I’ll do a 7yr update on the 12” Grendel as well. It has a duplicate sister in a 2A Balios Lite receiver set/handguard, so it’s interesting to compare the 2 as to how they’ve been doing. Same barrel and BCG in both. I connected 1st-round with the 12” Grendel at 900yds with 110gr PPU that I have not been able to get to shoot under 2.75” at 100yds. Figured it would just make close range fodder, but I went 3/3 at 780yds, then 1st-round at 900yds. Unbelievable...

Looking forward to the 12” update too!!

I’m in a similar position with the 6 ARC… I’m considering a 14.7” barrel as it’s pretty close ballistics wise to the 18” but a whole lot more compact. I like the idea of sending 108’s to 1k but realistically I’d like to launch them a long ways while shooting the 80 ELD VT’s flat to 400.

Will have to compare the 80 ELD VT trajectory to the 100 ELD VT’s out of the Grendel…

 

[bfoosh006]

LRRPF52, Thanks for all the info.

As for this part.. "When Hornady had the 200rd ammo cans of 123gr American Gunner, I packed my shopping cart full to the point that my little guy got evicted from the child seat, and the bottom rack of the cart was packed too. I miss $139.99/200 days for Hornady. Sportsman’s had a grand opening and Black Friday event with crazy deals that day in 2017."

That comment brought back fond memories....I did the same for the Horn. AG 140gr 6.5CM, same great price, from Sportman's, for a great inexpensive factory load.
I worried I might wear the barrel out , I shot so much of it. Lol

 

[towerofpower93]

LRRPF52, Thanks for all the info.

As for this part.. "When Hornady had the 200rd ammo cans of 123gr American Gunner, I packed my shopping cart full to the point that my little guy got evicted from the child seat, and the bottom rack of the cart was packed too. I miss $139.99/200 days for Hornady. Sportsman’s had a grand opening and Black Friday event with crazy deals that day in 2017."

That comment brought back fond memories....I did the same for the Horn. AG 140gr 6.5CM, same great price, from Sportman's, for a great inexpensive factory load.
I worried I might wear the barrel out , I shot so much of it. Lol

The one regret in my 6.5G life is only picking up 3 of the 200rd 123gr Hornady American Gunner ammo cans back in 2018/2019 when they were each ~$150 shipped. It was almost the exact same price for 600pcs of virgin Hornady brass, so why not get 600rds of training ammo while making a pile of brass for handloads? I'm sure the 600pcs of brass I have will last me for years, but having more of the AG ammo wouldn't have been a bad thing

 

[LRRPF52]

LRRPF52, Thanks for all the info.

As for this part.. "When Hornady had the 200rd ammo cans of 123gr American Gunner, I packed my shopping cart full to the point that my little guy got evicted from the child seat, and the bottom rack of the cart was packed too. I miss $139.99/200 days for Hornady. Sportsman’s had a grand opening and Black Friday event with crazy deals that day in 2017."

That comment brought back fond memories....I did the same for the Horn. AG 140gr 6.5CM, same great price, from Sportman's, for a great inexpensive factory load.
I worried I might wear the barrel out , I shot so much of it. Lol

Some of that was 6.5CM AG cases too that day, for friends when I saw the deal and sent them the pics. “Get me some cases too!!!” They had no limits on how many cases you could buy.

Good news is that Hornady Frontier 123gr is 81cpr right now, and Sellier & Bellot is 80cpr on ammoseek.

At one of my DM courses last year, a friend of mine made a 1st-round hit on a 760yd 2 MOA plate from his 12.5” Grendel with that 123gr American Gunner.

I saw factory Federal 77gr .223 for over $30/box at Cabella’s yesterday.

 

[VegasKyle]

I’ve got the same barrel. I had ADCO cut it to 16” and reprofile it for the Ops inc 12th model.

That barrel profile makes for a really light and handy rifle.

 

[jrhtx]

What velocities are you getting from the 17.6" vs the 12" with your loads?

 

[LRRPF52]

What velocities are you getting from the 17.6" vs the 12" with your loads?

For the 17.6” Grendel:

123gr A-MAX hand load on 31.2gr CFE223

2507
2492
2477
2496
2477

2490fps avg 64˚ F

Factory 120gr Scenar-L from PF

2505
2504
2453
2518
2498

2511fps avg

Factory Hornady 123gr SST

2451
2449
2473
2456

2457 avg

107gr SMK on 29.4gr 8208XBR
2626fps

94gr GMX Custom (cut down from 120gr GMX), 33.9gr CFE223, 2.261-2.275” COL
2749
2751
2741
2700

129gr ABLR on 30.7gr CFE223
2397
2400
2410
2393
2425

90gr Federal TNT Box ammo
2882
2886
2875
2878
2883

2900
2922
2903
2893
2904

2893fps (15ft from muzzle)

120gr Federal OTM box ammo
2441
2494
2492
2506
2491

2484fps avg

123gr American Gunner Hornady 200rd box ammo
2441fps avg
_____________________________________________________________________________________________

12” Grendel:

90gr Federal TNT
Unsuppressed
2702
2681
2670
2642
2654

Avg: 2670 @ 15ft, mv = 2685fps

Suppressed w/TBAC Ultra 5
2675
2658
2660
2671
2685
2723
2700
2690
2682

Avg: 2683 @ 15ft, mv = 2698fps

120gr Federal American Eagle OTM

Suppressed
2411
2398
2397
2349
2406
2384
Avg: 2384 @15ft mv= 2393fps

I’ve been shooting factory ammo through my 12” exclusively since 2017, mainly 123gr ELD-M, 90gr TNT, 120gr Federal OTM, and 110gr PPU. I just used box published mv, then ran that through an internal ballistics engine from Shooter’s Notes, and I usually connect 1st or 2nd round at 780yds with it that way. I’m using the GRSC Norden Performance 1-6x24 LPVO with the GRSC reticle.

I also loaned it out in one of my DM courses to a guy who brought a case of Wolf steel, which he shot through it for 2 days.

A good comparison is that 90gr TNT, where the 17.6” is basically shooting it at 2900fps, and the 12” at 2700fps.

I need to chrono the new Hornady 100gr ELD-VT, but I never missed with it at 1000yds when I took it out a few weeks ago through the 17.6” Lilja. I first-round connected with it at 700yds, went to 800yds....1st-round, skipped 900 and went to the 1000yd gong.

Shot a group that turned out to be impacting low and right on the gong, adjusted to centerline and finished out a good string on it to see if it was consistent. Let my boy shoot it and he was 4/5 at 1000yds, first time ever shooting that distance in his life (8yrs old).

 

[jrhtx]

Thanks!

 

[LRRPF52]

Another thing I wanted to point out is that the only scope and mount I have ever put on it is what you see:

Vortex Viper PST 2.5-10x32
NightForce Unimount 20 MOA

That scope has held zero, tracked back and forth through endless rotations for elevation changes ranging from 100-1000yds across a wide range of environmental extremes. Every time I dial it to the indicated dope from my ballistics program, I’m center-punching steel with the 123gr A-MAX and ELD-M loads. It has the old school shim zero stop in it, which has worked fine for me all these years.

It has been used in everything from hot/dry/high altitude to below-freezing, windy, and snow storms:

 

[TwoRs]

Thank you! Great info

 

[towerofpower93]

Another thing I wanted to point out is that the only scope and mount I have ever put on it is what you see:

Vortex Viper PST 2.5-10x32
NightForce Unimount 20 MOA

That scope has held zero, tracked back and forth through endless rotations for elevation changes ranging from 100-1000yds across a wide range of environmental extremes. Every time I dial it to the indicated dope from my ballistics program, I’m center-punching steel with the 123gr A-MAX and ELD-M loads. It has the old school shim zero stop in it, which has worked fine for me all these years.

It has been used in everything from hot/dry/high altitude to below-freezing, windy, and snow storms:

View attachment 8385164

View attachment 8385165

View attachment 8385166

I had a couple SFP 2.5-10x32 Gen 1 Vortex PSTs back in the day and loved them. I eventually sold them when I went to MILs and FFP on everything for the sake of commonality, but those scopes did well for me on rifles used for 2G, 3G, and DMR matches. I'd also take the 18" DD upper that was wearing one of the 2.5-10x PSTs to the occasional 1000yd belly flop match when I wanted to see just how good I was at reading the wind with 77gr SMK handloads (spoiler, I wasn't ).

 

[LRRPF52]

Someone asked if I chronorgraphed the 100gr ELD-VT yet, which I have shot a bit out of this 17.6” Grendel. Some very interesting findings have come up.

I didn’t chrono it, so I took the box data of 2730fps from a 24”, plugged it into a Grendel internal ballistics engine, and got 2598fps for my 17.6”.

I used that and plugged it into my program, 1st-round connect at 700yds, dialed to 800yds, connect, went to 1000yds where we finished out water-lining it. Initial drop prediction for 1000yds was low and right on the target, so I adjusted up to centerline with the group, which ended up being 10.8 mils. It was pretty cold at about 20˚F if I remember correctly.

Truing it with Hornady’s program to 10.8 mils at 1000yds in the conditions I was in, it’s showing a mv of 2590fps from the 17.6” barrel. I just looked at 6mm ARC in that weight and this is basically duplicating or exceeding it. If you shot the 103gr ELD-X 6mm from ARC from an 18” at 2575fps, it has more drop and drift than what I’m seeing from the 100gr ELD-VT 6.5mm at 2590fps. You have to go to the 110gr A-TIP to get below the drift it seems. 108gr ELD-M didn’t do it when I ran it through the 4DOF Doppler program.

Weird. So this 100gr ELD-VT is like 6mm ARC performance without needing to make the switch. I just double-checked that I entered in all the same variables for the conditions, and I’m using real-world drop and impact data that I recorded from the 17.6” Grendel shooting factory Hornady 100gr ELD-VT.

 

[rlsmith1]

Someone asked if I chronorgraphed the 100gr ELD-VT yet, which I have shot a bit out of this 17.6” Grendel. Some very interesting findings have come up.

I didn’t chrono it, so I took the box data of 2730fps from a 24”, plugged it into a Grendel internal ballistics engine, and got 2598fps for my 17.6”.

I used that and plugged it into my program, 1st-round connect at 700yds, dialed to 800yds, connect, went to 1000yds where we finished out water-lining it. Initial drop prediction for 1000yds was low and right on the target, so I adjusted up to centerline with the group, which ended up being 10.8 mils. It was pretty cold at about 20˚F if I remember correctly.

Truing it with Hornady’s program to 10.8 mils at 1000yds in the conditions I was in, it’s showing a mv of 2590fps from the 17.6” barrel. I just looked at 6mm ARC in that weight and this is basically duplicating or exceeding it. If you shot the 103gr ELD-X 6mm from ARC from an 18” at 2575fps, it has more drop and drift than what I’m seeing from the 100gr ELD-VT 6.5mm at 2590fps. You have to go to the 110gr A-TIP to get below the drift it seems. 108gr ELD-M didn’t do it when I ran it through the 4DOF Doppler program.

Weird. So this 100gr ELD-VT is like 6mm ARC performance without needing to make the switch. I just double-checked that I entered in all the same variables for the conditions, and I’m using real-world drop and impact data that I recorded from the 17.6” Grendel shooting factory Hornady 100gr ELD-VT.

Did you run anything for sub-500y distances? I'm getting 2850fps out of my 18" 6 ARC and 80's, and really like that trajectory for night yotes (22 ARC is better for that but I don't want to give up the ability to shoot the heavies)

 

[Cascade Hemi]

Someone asked if I chronorgraphed the 100gr ELD-VT yet, which I have shot a bit out of this 17.6” Grendel. Some very interesting findings have come up.

I didn’t chrono it, so I took the box data of 2730fps from a 24”, plugged it into a Grendel internal ballistics engine, and got 2598fps for my 17.6”.

I used that and plugged it into my program, 1st-round connect at 700yds, dialed to 800yds, connect, went to 1000yds where we finished out water-lining it. Initial drop prediction for 1000yds was low and right on the target, so I adjusted up to centerline with the group, which ended up being 10.8 mils. It was pretty cold at about 20˚F if I remember correctly.

Truing it with Hornady’s program to 10.8 mils at 1000yds in the conditions I was in, it’s showing a mv of 2590fps from the 17.6” barrel. I just looked at 6mm ARC in that weight and this is basically duplicating or exceeding it. If you shot the 103gr ELD-X 6mm from ARC from an 18” at 2575fps, it has more drop and drift than what I’m seeing from the 100gr ELD-VT 6.5mm at 2590fps. You have to go to the 110gr A-TIP to get below the drift it seems. 108gr ELD-M didn’t do it when I ran it through the 4DOF Doppler program.

Weird. So this 100gr ELD-VT is like 6mm ARC performance without needing to make the switch. I just double-checked that I entered in all the same variables for the conditions, and I’m using real-world drop and impact data that I recorded from the 17.6” Grendel shooting factory Hornady 100gr ELD-VT.

107TMK is almost identical and has been around for 7 or 8 years

 

[LRRPF52]

Did you run anything for sub-500y distances? I'm getting 2850fps out of my 18" 6 ARC and 80's, and really like that trajectory for night yotes (22 ARC is better for that but I don't want to give up the ability to shoot the heavies)

90gr Factory Federal TNT does 2900fps from the 17.6” Grendel, but the 6mm 90s have better BCs for sure.

I have some 6.5mm 80gr Monoliths on the way to experiment with. I think the 6mm really makes sense in that varmint-slayer and double duty as a smaller deer killer with those 75gr-90gr weights, though you won’t see much difference shooting 80-107gr from the Grendel within 300-400yds. Both will give you more capability than a .223 Rem in that application (varminting and medium game).

The 100-110gr bullets in 6.5 Grendel are noticeably-flatter than 123gr even at distances well past 500yds.

 

[Stockman]

Am I confusing this 17.6” with the Lilja WASP profile that is prominent in your AR15.com thread?

 

[LRRPF52]

Am I confusing this 17.6” with the Lilja WASP profile that is prominent in your AR15.com thread?

Same blaster. I built it in 2014 and have been regularly shooting it ever since, stacking a pretty hefty round count on it.

Last range trip, I 1st-round center-punched a steel plate with one of my old CFE223 hand loads I found in a box I had forgotten about. The Vortex 2.5-10x32 FFP PST tracked perfectly after all these years of dialing up and down from 100-1000yds repeatedly. The thing feels like an old school 727 barrel profile M4A1, it’s so light.

Even though the barrel has a .650” profile under the handguard before the shoulder for the gas block, it still shoots like it did the day I first grouped it. 3rd groups are in the .3s, 5rd in the .7s to .9s, 10rd in the 1.2s. Can’t ask for more than that with how light it is.

 

[ARShooter91]

My 6.5 Lilja has at least 2500rds on it and the throat looks brand new still. Never measured lands and I'm sure they've moved a bit but it's still super smooth in there.

 

[LRRPF52]

My 6.5 Lilja has at least 2500rds on it and the throat looks brand new still. Never measured lands and I'm sure they've moved a bit but it's still super smooth in there.

That’s one thing I’m wondering about since I know I have the compound throat in it that starts with a .5˚ leade, then transitions to a 1.5˚ leade.