Sniper & Sharpshooter Forums banner

41 - 60 of 1013 Posts

·
Registered
Joined
·
4,851 Posts
Old eyes, fat fingers and late night. Small mind ? Perhaps. The correct oal is 2.920 base to tip. Base to ogive is 2.345.

Sounds like a stock Remington chamber:cool:

If so, you're lucky you were able to get that close to the lands and still have enough bullet in the case neck.

I got tired of that with my old remington barrel so I had the new chamber cut/throated so I could load to magazine length and still be .020 off the lands with a 175 SMK. I bought a "Repeater" so why not be able to use it as such. Even added a mag extension so I can stuff 7 rounds "in the box".
 

·
Registered
Joined
·
6,268 Posts
Did you pick up any accuracy?

In my experience, the 175SMK is so jump-tolerant, that it rarely makes a perceptible difference. Are you saying you cut a NEW barrel chamber to your specs, or set back your old one?
 

·
Registered
Joined
·
4,851 Posts
Did you pick up any accuracy?

In my experience, the 175SMK is so jump-tolerant, that it rarely makes a perceptible difference. Are you saying you cut a NEW barrel chamber to your specs, or set back your old one?

Brand new Barrel. Dropped off the old barrel/action at Benchmark and told them to call me when it was trued with a new 24" 5-C barrel on it. Was easy as they are located only three Freeway exits from me. The only "set back" was to my wallet:cool:


They used a "no-turn" match reamer which gives me minimal clearance on a new case at the neck, a nice tight freebore (.3085") and minimal throating.

Accuracy is superb. The profile is supposed to be a #7 but not sure "who's" #7. Heavier at the breech end than the old 5-R milspec but still has the same muzzle dia. First shot is as accurate (even cold bore) as the 50th shot.
 

·
Registered
Joined
·
9 Posts
Remington Model 700 AAC

Hornady 178 A-Max
43gr Varget
Federal 210 Match Primers
 

·
Registered
Joined
·
4,851 Posts
Found a good supply of IMR 8208 XBR so I decided to work up a load for my 175 gr SMK's I like to have a few "recipes" so I can use whatever happens to be available.

The load:

175 gr SMK
Lapua 3-4 X fired brass, annealed, trimmed, and F/L sized Total indicated runout on case necks <.001".
Federal GMM primer
42.2 Gr IMR 8208 XBR

Estimated Speed ~2630 fps (Will chronograph next time at range)

The Rifle:
Remington 700 that started life as a 5-R Milspec (with Stainless Steel Action)
Benchmark 24" 5-C Barrel chambered with "No Turn" Match Reamer
Bell and Carlson Medalist Varmint/Tactical Stock
Sinclair Tactical Bipod
NightForce 12-42X56 NXS Scope
Birdshot bag filled partially with sand for rear bag.

The results:





This was shot at 200 yards on a morning with fog coming and going. At times the other shooters had to stand down as they couldn't even see their 300 yard targets. I was able to just make out the orange circle and had to wait for the dot in the center to appear before pulling the trigger. The last shot was the one at the right which I fired just as the target disappeared from the scope, totally.

This was part of a workup. 5 shots per load in .3 gr increments. Started at 41 gr and was totally discouraged as the test progressed. All of a sudden, this group popped up and it's only .2 gr below published max. Rest were OK for knocking down game inside of 300 yards but not good enough for me.

Using "On Target", the 4 shot group measures a max spread of .224 MOA with an Average To Center measurement of .101 MOA. Actual measurement of the group was .469" and again, shot at 200 Yards.

When I add the 5th shot the group opens up to .457 MOA but the Average to Center remains lower at .152 MOA.

Considering that this was shot in the fog I'm good with this and am going to keep this load. Considering the "temperature resistance" of the 8208 XBR it may well be my "Winter Load". Who knows, if it keeps shooting like this for me I may even stop using Varget (like I could even buy more if I wanted to right now)

BTW, the "42 & 42.4" notes are what I'm going to use to verify this load. May even get smaller with just a little more, or just a little less.
 

·
Registered
Joined
·
4,851 Posts
I'm loading 175 SMKs over 41.8 grains of 4064 Lapua brass 210 fed primers.
Remington 700 police 26" 1 in 12

At 100 yards.
View attachment 2142

At 300 yards.

View attachment 2143

Jut a suggestion based both on advice given me by an experienced (and winning) BR shooter, and my own experience. When a group is vertically strung like the top one (which is still a nice group), try a little more powder. The person offering the advice to me had a standard rule-- "Vertical? Add more powder. Keep going until it squeezes into a triangle or single hole."

My personal experience with same components that you used puts my loads in the low to mid 40's.
 

·
Registered
Joined
·
750 Posts
This is follow up to post #20, using IMR 4064 powder,175gr SMK, WLRP’s and once fired FGMM brass. The major difference between this test and the test on #20 was that the OAL was stretched out to 2.880”. This length was chosen because this length will still function in my AICS magazines. Foggy morning.
 

Attachments

·
Registered
Joined
·
39 Posts
Thanks to everyone . This is a great thread. I was able to finally et some testing time. The group was fired from a mat with my left arm as support. a little over 100 yards. very satisfied with the first results. This was fired with my pre 1980 Savage 110S. the rifle has been bedded, and has a floating barrel. 308 group.jpg
 

·
Registered
Joined
·
36 Posts
Is there a reason why 175gr bullets seem to be the most popular in here? Are they just easier to come by, or is it all personal preference?
 

·
Registered
Joined
·
330 Posts
This was part of a workup. 5 shots per load in .3 gr increments. Started at 41 gr and was totally discouraged as the test progressed. All of a sudden, this group popped up and it's only .2 gr below published max. Rest were OK for knocking down game inside of 300 yards but not good enough for me.
Just curious, deadshot, since I just got some xbr8208. Your text says you used 0.3 grain increments in your load workup but you included 42.4. That doesn't fit in the progression from 41 - was that a typo or do you vary your increments?
 

·
Registered
Joined
·
6,268 Posts
It's not just the better BC that comes into play. It has to do with the overall bullet design. The 168's tend to destabilize sooner, making them less predictable as you approach 1000yds in the lower elevations. The 175's do not exhibit these problems.
 

·
Registered
Joined
·
330 Posts
It's not just the better BC that comes into play. It has to do with the overall bullet design. The 168's tend to destabilize sooner, making them less predictable as you approach 1000yds in the lower elevations. The 175's do not exhibit these problems.
Does this destabilization also apply to the Berger 168 Target Hybrid? It has a higher BC and a design that differs from the more common SMK 168.
 

·
Registered
Joined
·
4,851 Posts
Just curious, deadshot, since I just got some xbr8208. Your text says you used 0.3 grain increments in your load workup but you included 42.4. That doesn't fit in the progression from 41 - was that a typo or do you vary your increments?
As I got closer to the max I varied the loads slightly trying to sneak up on max rather than having it slap me in the face. I "split the difference" between 42.2 and 42.6. I follow the advice of an old BR shooter that always says "if you have vertical dispersion, add more powder". That's what I was doing but was coming up against the "max" (at least for me).
 

·
Registered
Joined
·
4,851 Posts
Does this destabilization also apply to the Berger 168 Target Hybrid? It has a higher BC and a design that differs from the more common SMK 168.
Do some reading on Brian Litz's work on "bullet form factor". Bullets with a given form factor (Sectional Density as related to G-7 BC) tend to remain stable far longer in flight than others. It isn't just a function of bullet weight but also bullet length.

If shooting Long Range one should look more at G-7 BC's as they more truly represent the performance of modern bullet designs.
 

·
Registered
Joined
·
6,268 Posts
Does this destabilization also apply to the Berger 168 Target Hybrid? It has a higher BC and a design that differs from the more common SMK 168.
I was referring to the 168SMK. Sorry, I should have been more specific.

I've not spent a lot of time with the berger 168, so I wouldn't be able to comment.
 
41 - 60 of 1013 Posts
Top