Home Forums Hunting & Shooting Long Range Hunting Sierra 183gr in 7mm

Anybody shooting these with a standard 1:9 1/4” twist?

Sierra tech says need a 1:8” minimum. Hoping someone has some experience.

I want to know results too

Going to be in Sedalia tomorrow and planning on going by the outlet store. Called today and the nice lady said that was about the only 7mm bullet they had in stock. May just buy a couple pounds and try.

Let me know how they do please

My 7mm rem mag seems to have trouble with the 175 eldx. At least it shoots them poorly in the 4-5 different loads I have tried. Now the 175 partitions and 175 hornady sp .7 moa. 175 eldx maybe 1.5-2 moa at best. Mine is a sako 24 in barrel 1-9.5. With retumbo got the 175 eldx to well over 3k but no accuracy. I would guess it will have a little trouble stab those long pills.

Do some measuring and run the numbers through the Berger twist calculator . I bet the are marginally stabile at best in a 1-9.5" twist. Depending on elevation a 1-8.5" is probably minimum.

From the front yard of our NC PA camp we can pretty much pick the distance from 400 yards out to over a mile.
Needless to say that over the last 50 years thousands of rounds have been sent at various rocks on those hillsides.
Fifty years ago, we were using the 162 gr Hornady match BT bullet in our 7 mm mag Rems and our 7x300 Wetherbys, and later our 7 mm Ultra mags.
When Berger introduced the 180 gr 7mm bullet, everybody was clamoring to get them, because they were of the opinion that the heavier higher BC bullet would improve their guns.
Mind you i had a large stash of the 162s, so i was in no hurry to even try them.
But my engineer grandson was very interested in trying them in his 7 mm ultra mag, so he bought a box of them.
Now for those who have never owned one of those cartridges, the 7 mm ultra mag, the 7 mm STW, and the 7x300 Wetherby are all pretty much clones from the velocity standpoint.
Anyway we loaded up some of the bullets for both the 7x300 and the 7 mm ultra.
We then used our old charts for dialing for a 1200 yard rock we shoot at alot and sent one of the 162s over there.
Then without changing the scope settings we sent one of the 180 Bergers.
The 162s in both guns were a good foot higher than the 180s were.
So there is no question that velocity trumps a higher BC at least to some point.
And the point also is, after a certain distance with any cartridge, there is no point to a heavier higher BC bullet.
Move on to a larger case holding more powder if you want more performance.

Did you check for POI differences at your zero distance? That will certain affect any POI difference at extended distance. Regardless, difference in drop is not really the point of choosing a high-BC bullet. How did they compare in wind drift?

Your comment about velocity trumping BC depends entirely on the difference in muzzle velocity and the difference in BC, as well as the distance at which they are compared.

Your final point is actually the opposite of the truth. BC advantages become more and more evident as distance increases.

WeWell yes, actually we are aware that different bullets require different zeroing.
And the differences at 100 yards arent always much different are they?
And yes BC has more advantage (provided) there is velocity to sustain it.
But im just relating our experience, and i would suggest that others do like wise.
Rather than just swallow a bunch of gobbley goop your apt to read on the internet.
The bigger issue is that there comes a point where the cartridge were using is simply out of gas.
And a higher BC number on the box wont help that, at least in the amount many think it will.
And our testing proved that at least to us.
Again, i strongly suggest that others do likewise.
Otherwise there would be no need for cartridges like the 7mm ultra mags.
A 7mm Rem mag with higher BC bullets would be all thats necessary.

OK, you're aware. But did you actually rezero? A half inch at 100 would eat up 6 inches of your observed difference at 1200.

Most of the time, the difference in zero at 100 yards becomes a substantial difference at 1000+.

Not sure I understand your point here. BC is simply a number that quantifies the relative drag forces a particular bullet experiences when in flight. Simply put, the higher the BC value, the less a bullet’s muzzle velocity will be lost in transit to the target, and the less the bullet is affected by the air (including wind). Velocity is a diminishing resource, while BC, like a diamond, is forever (relatively speaking).


Testing is important, but its utility depends critically on understanding what is being tested and the results. Otherwise, incorrect conclusions are drawn, and faulty reasoning embraced. Testing the effects of changing certain variables (like bullet and muzzle velocity) on something like trajectory, requires other variables (like zero distance) to be controlled for meaningful results to be obtained.


That entirely depends on how you define “out of gas,” “need,” and “necessary.” Higher BC absolutely will help a bullet arrive at a given distance with higher impact velocity and kinetic energy, and less wind drift and drop. Large BC differences lead to substantial gains. Indeed, a 7RM shooting high-BC bullets is superior to the 7RUM shooting low-BC bullets much faster, depending on the criteria. Beyond a certain distance, the 7RM bullet will have higher impact velocity, more impact energy, less wind drift, and its trajectory will flatten out more, as well.

I am not a long range shooter at all. Never even taken a shot over 350 yards. But discussions like this have educated me to the advantage of using the highest bc bullet in any weight I chose. It's like getting free velocity and power without the recoil. It maximizes what you start with.
As long as the bullets construction is adequate for the game or task it's used on, it provides bonus performance at no extra cost. Thanks guys.

The bc debate is fun. The one factor to also consider is accuracy. I have several guns that definitely shoot flat base bullets far better than bt. Bearing surface is supposed to be the reason why. Normal hunting the bc is kinda irrelevant. Loooong range is a different story because of wind. Edk

You are a Lying CLUELESS Drooling Piece Of Fhuqking Schit. Hint.

Where and how do you Fhuqking Retards DREAM this schit up?!? Hint.

Fhuqking LAUGHING!..............

Reading these type of threads makes my head spin. It's a WTF moment when you realize how many people just can't grasp the idea of BC and how it affects ballistics... or how to properly test for these advantages.... SMH....

No dog in this fight..and there was no mention of velocity for either bullet, but a simple check with Hornady Ballistic Cal. indicates a 7mm 162 gn. BTHP at 3100fps needs 33 MOA to reach 1200 yrds. The 180 Berger at 2900 fps, needs 34.2 Bump the Berger up 100FPS, and things begin to change. But that`s about the "foot" he saw.

A 180 ELD M has a BC of .796. Hint.

Physics ain't "subjective". Hint.

Just sayin'................

The wind drift will be more with the 162 grain

Per the Calculator, 10mph full value, 8 MOA for the 162, 7 MOA for the 180.

Finally took the time to give these a go. 67.0 gr Magnum powder, CCI250, Norma brass. OAL 3.500”

Rem 700 in ADL, factory. McMillan HTG stock, seekin ring/base mounting an Athlon 2-12.

Temp 82, crosswind 5-8 mph

This is three 3-shot groups. 9 total shots fired in about 15 minutes total elapsed time. Never changed aiming point, but tried to watch wind and get as close to consistent as possible. 200 yards