flat base or boat tail for .308?

[1858rem]

i am trying to work a load for a 788 in .308 i have....i messed up the pressure point in the stock and am still working that out,

in the meantime i used up all but about 30 of my bullets that work well which happen to be some remington psp corelokt i got on sale,

but they all have groves in various places up front like they are pulled bullets maybe, and there was two distinct groups of bullets with the cannalure about 1/8" high or low variations,

and i have fewer than 60 150g sst left that i cannot get to group well even though they have a much higher BC and WAY more uniform look as far as ogive and jacket texture....but then there is the gun still i think is throwing my groups off.

so i need to order some more bullets, i looked at the hornady 168 bthp and decided to maybe try a box and see how they do since it appears my gun prefers the 165g over 150.....

i plan on ordering three boxes at less than 80 dollars total, the 168 bthp are on sale now and are well within this range so should i get 300 of them, or try a different flat based design like the 165g that work ok (which for me is 1 1/8" for 8 shots at 100 yds) i prefer not to use the core lokt since i plan on shooting at milk jugs an targets out to about 500 yards and i dont think they would do to well with all the odd dents they had.

<mini off my main topic rant>
or should i give up on this 788 for now and load up on bullets for my .204 that'll shoot one holers easy(which is really small compared to a .30cal one hole group)? i wanted to have a good long range gun capable of at least 1"@100yds(which when i got it this one was:banghead::banghead and was hoping i could change bullet selection instead of settling for an average 2.5" which is only as good as i could shoot the 30-30 WITHOUT a 4-16X40mm scope on it, plain old open sights and i get the same from a 30-30...and thats only the second time i shot the mod 94!!! gettin so PO'd at this rifle

 

[NCsmitty]

IMO, it's foolish to order all of one type of bullet if it has not been proven to shoot in your rifle.
It seems to me that you shouldn't blame the rifle for a situation that you created. Most 788's that I've seen shoot very well.
My priority would be to sort out the problem with the rifle before continuing with the load development. It should not be that difficult to solve if you give it your attention. You need to bed the action and float the barrel OR bed the action and barrel, at least part way. One of those procedures should work to give you an idea what's going on.
I float all my centerfire rifles so a dollar bill will slide all the way to the action.

NCsmitty

 

[dirtman]

That 788 in 308 is a good ole gun.. i still have one that i use regularly.. always got good 100 yd gps.. about 1/2" or better.. using hornady 165s #3045 btsp.. with 44.2 grn of 748 or 41.6 grn of 3031 fed mag primer with 748, this is also a great hunting rd. good luck

 

[1858rem]

i had free floated it to where i could run an index card all the way to the lug in the stock

*which btw had about 1/16" travel collectively, side to side.... so ran some electrical tape around the lug to snug things up and that didnt seem to help.....but with the two screws that hold the barrel and action to the stock should the loosness even be a problem*

sorry but i have the bad habit of straying off my own topics,
i had the barrel floated, got 3" or so groups at 100 yds that went in a circular pattern, read here about adding the pressure point for a reason so i doubled over an index card and slid it under the barrel and then got eight shots off in about 5 or ten minuets that all went into 1 1/8" even as the barrel heated, with the first and last shot within half an inch...im so close to getting it back to normal, but working on the permanent part of that deal.




the 165 do shoot good, the 168 bthp just went to backorder and im not payin an extra 13 bucks to get them shipped LATE! so i think ill look for some flat based 165, but i did see some spire point boat tail 165 also reasonably priced, is the boat tail going to make it more difficult to find a load with or is it the same as flat based loading?

 

[1858rem]

i noticed that it was only the crease in the index card that was adding pressure to the barrel,but the crease was also not only adding pressure to the bottom of the barrel(like i recently did with a dowel trick) but also all the way around the barrel......should i try to replicate the same effect... added pressure all sides of the barrel and not just the bottom?

dirtman,
how picky is your 788 about ammo?

geez just checked again and nearly everything is on backorder so i think i will try one box of nosler custom competition 168 bthp on this order and focus everything else mostly toward the .204

 

[Sport45]

but they all have groves in various places up front like they are pulled bullets maybe, and there was two distinct groups of bullets with the cannalure about 1/8" high or low variations,

Sounds like you are shooting pulled or surplus military bullets. The cannelure is in a different place for the M1 (30-'06) vs the M14 or M1A (.308). Do you have any bullets with both cannelures? That's usually a dead giveaway. These aren't match bullets but should hold 1-1/2 to 2" at 100 yards.

 

[1858rem]

none with both cannelures, but they were in a repackaged components box, and they still shot better than the sst's did which really confused me, although i have not really shot many of the sst's.

how much accuracy difference can there be between loads?
i was thinkin loading up 10 of the 165's w/44.5g RL-15

and ten of the 150's with 45.5 grains of varget as baseline loads to see what changes im making to the gun.... can half a grain either way can throw the group an extra inch wide or something on that order? one reson i asked about FB vs. BT was i thought that the BT bullets could be really load specific like that, compared to the flat based bullets anyhow

 

[NCsmitty]

*which btw had about 1/16" travel collectively, side to side.... so ran some electrical tape around the lug to snug things up and that didnt seem to help.....but with the two screws that hold the barrel and action to the stock should the loosness even be a problem*

Are you saying that you have movement side to side after you tighten the action screws, or am I misunderstanding you?

NCsmitty

 

[1858rem]

yep sure is, was anyhow...

last night i built a u shaped wooden insert to put under the front of the barrel to add pressure on all three sides, and now there is no travel either way... i doubt i have 10 lbs of pressure on it, but is it possible to have too much because i dont really have a way to gauge the actual pressure applied, but say if im within 5 lbs +/- of the goal ten lbs will it still work the same?

 

[NCsmitty]

A shim under the barrel is not going to fix the inherent problem of a loose action. You will never get good permanent accuracy with a loose action regardless of the shims that you use. The action lug needs to be bedded to prevent that movement.
If you cannot do it then have someone who can. Your problem is the action, not the barrel.
You are trying to take a bandaid approach to the problem. The rifle deserves better, and I'm sure you'll be amazed in the difference it makes.

NCsmitty

 

[dirtman]

"how picky is your 788 about ammo?"

Don't know.... for the last 25 + yrs been shooting the same round as above mentioned. I have a few 308s and i like them all.. I bought this 788 new mostly cause it was cheap and would be a good trunk gun in my travels around farm country. but the darn thing was so accurate that i found myself using it more and more... when new it could do constant 1/3 " at 100 yards... I can’t remember what all I tried in this gun it seemed to like anything but the 165’s were really nice. and those loads are easy on brass. but also have taken a few elk for me and lots of every thing else.... + 1 for “A shim under the barrel is not going to fix the inherent problem of a loose action.” work that out and u likely got a very good gun...
308’s seem to eat just about any round you throw at them... all the best and have fun cleaning that 788 up...

 

[1858rem]

oh, darnit! i already put my order in:banghead:. i had a bedding kit in my cart, but after the $77 of powder i got it would have been over my budget/month and decided not to get it. i shot three of the sst off today and it was the first time i ever put them all under an inch! but i guess ill see if dad will lemme borry the road king an all cruise around the gun shops and see what they got an that department........of course i could just call and ask, but whats the fun in that

 

[1858rem]

well i ended up getting the nosler CC 168 bthp, any suggestions for a good bedding kit that would be in your typical gunstore?

 

[godsey5]

Use the acra glass kit. I've done several rifles with good success. Use the gel it is easy to work with and use plenty of release agent.

jim