Lija barrel question

[cst]

I'm thinking of ordering a barrel from Lilja..unfortunately I missed the group buy..But I got 2 questions..
Im split between the (18.88")319 and the 318 countour and the same coutours with rifle length gas...

I guess the first question is a barrel with .825 diameter under the handguard vs the .650...any drawbacks or advantages? besides weight...I know the thinner countour would heat up faster but any loss of accuracy? etc...?

and the next question is the mid vs. rifle length gas system... but would there be reasons people would prefer mid for 18,19" rather than rifle? I'm new to the 6.5 and I assume as long as the gas port is appropriately sized, a rifle would be just as reliable? what am I missing?

[cory]

Around last august we had an entire thread on gas length system for the Lilja group buy. Long story short you want to go with the midlength gas system for an 18" barrel. IF it helps you finding the thread I started it.

[explorecaves]

I know it will take some time, but these questions were answered in the Lilja group buy thread. Also, I believe there is discussion about this in the grendel reloading handbooks (don't have them in front of me to verify).

[cst]

I get the midlength gas system....I am alittle rushed to go thru all the pages of the group buy(I got to get back to Lilja ASAP) can anyone summarize any other key things I may have missed especially the barrel countour? I'm split between the heavier .825 vs. .650 under the handguard..I'm building a SPR competition rifle....

appreciate it!

[explorecaves]

What is the specifics on the competition? Mainly bench or more run and gun?

midlength
< 16" barrel = short stroking
16-18" = ideal
>20" = early unlocking

rifle length
< 18" barrel = short stroking
18-24" = ideal
>24" = early unlocking

[cst]

thanks man! I appreciate the quick summary!!

[cst]

My reloading handbooks just came in the mail 5mins ago!! time to read..

[Tedward]

Less available Gas Blocks for either the .875 or .625. .750 would give you more options.

[explorecaves]

Less available Gas Blocks for either the .875 or .625. .750 would give you more options.

Yup - if you want the gas block covered by the hand guard, go with .750 or .625.

[cory]

If you can find the main Lilja Group Buy Thread (~600+ posts) The original post has a layout of how many of which contour was ordered. It'll give you an idea of how everyone leaned after all the discussions on contours.

[cory]

Actually here you go.

M4 0
AR740 31
AR24 12
303 0
318 8
304 11
310 0
319 7
311 6

[dmsims21]

About an even split between the 318 and 319 - they seem to be equally desirable.
I got the 319 (.825 under the HG). The .65 under the HG should be fine, but I don't like how it is .75 after. I fundamentally don't like the profile ending larger than the middle.
I guess it is the engineer in me, but cantilevered beams should start with a large cross section and end with a smaller one.
"Its science"

The Lilja barrels are properly stressed relieved, so even the lighter profile shouldn't shift POI when it heats up.