Here is an excellent write up on 7mm-08 bullet selections for game sizes , desired hunting distances, and environmental conditions.
Remington’s 120 grain hollow point is designed for varmint hunting but is adequate for game as heavy as 40kg (90lb).
The 140 grain Core-Lokt load has a jaded history. Initial velocities for this load were very low and produced poor case neck to chamber obturation along with excessive powder fouling at the neck and throat area of rifles. The compacted powder residues raised pressures while destroying accuracy. Velocity was in the region of 2650 to 2750fps and with the extremely poor BC of .390, the Core-Lokt load did not run true to the advertising claim that the 7mm08 produced superior ballistics to the .308.
The current 140 grain Core-Lokt load achieves a velocity of around 2800fps in 22” barrels, slightly but insignificantly lower than 24” test barrel velocities.
While its BC may be poor, performance on game out to moderate ranges is excellent. For hunters who seldom take shots beyond 200 yards, the Core-Lokt is inexpensive yet highly effective, producing both broad wounding and reasonably deep penetration with minimal risk of jacket core separation.
The more recently introduced 140 grain Accutip is quite different to any former Remington loadings. Remington made an effort to ensure this load achieved maximum velocities along with desirable longer range performance. The only downside is that this load is terribly expensive for U.S hunters, let alone export countries where one packet of Accutip ammunition can cost the same as a weeks groceries for a single man.
At close ranges, the Accutip (which is most likely a re-branded SST), produces immensely traumatic wounding on medium game. This is not an Elk bullet, doing its best work on all game up to weights of around 80kg (180lb).
Penetration is fair at close ranges although retained bullet weights tend to be lower than 50%. At longer ranges, the Accutip can suffer jacket core separation but at such ranges (250 yards and beyond), this behavior is not usually detrimental to wounding as the bullet fragments are large and lethal. From a velocity of 2840fps, the Accutip does its best work inside 250 yards (2400fps). Beyond this range, the bullet design and power of the 7mm08 limit wounding although kills are normally clean, even if delayed. Performance is reduced further at 375 yards or 2200fps.
Federal have really gotten behind the 7mm08 in recent years and now produce several useful loads. These include the 140 grain Nosler Ballistic Tip at 2800fps, the 140 grain Accubond at 2800fps, the 140 grain partition at 2800fps, the 140 grain Barnes TSX at 2820fps, the 140 grain Fusion at 2800fps and finally, the 150 grain Speer Hotcor at 2650fps. For unknown reasons, all of these loads achieve velocities faster than the above advertised specifications regardless of the fact each were developed in a 24” test barrel. From typical 22” barreled sporting rifles, Federal’s 140 grain loads achieve 2840fps while the Hotcor achieves an outstanding 2750fps. None give excessive pressure and all have the potential to produce outstanding accuracy in suitably tuned rifles.
The 140 grain Ballistic Tip is, as can be expected, a general purpose open country load. Wounding is thorough and violent at closer ranges, killing is clean but in no way spectacular. For smaller species of Whitetail and other game of this size,
the BT is an ‘adequate’ performer out to ranges of 350 yards. On small but tough animals such as pigs, the BT can be quite shallow penetrating and wounding limited by the power of this cartridge. It should be noted that Nosler’s original ideal bullet design was the Partition, the Solid base and later the Ballistic Tip created to meet trends, rather than performance orientation.
The Accubond is another humble performer producing wide internal wounding and clean killing but with relatively deep penetration. Hunters should not expect exceptionally deep penetration with this bullet as it has a very low SD. As a medium game bullet, the AB is a good all-rounder.
The 140 grain 7mm Partition is much like the Accubond, both produce a wide wound regardless of the focus towards optimum controlled expansion within each design. Again, a low SD as a result of the 140 grain 7mm bullet weight dictates that for best performance, the Partition and Accubond do their best work on game weighing up to 80kg (180lb). Both bullets are adequate for game up to 150kg (330lb) but this weight should be considered a maximum.
The Accubond and Partition often produce surprising good performance at lower velocities of 2200fps or 300-350 yards providing game are not too lean.
The stoutest bullets in the Federal line of ammunition are the 140 grain Barnes TSX and the 140 grain Fusion loading. The Fusion bullet is a very odd, almost rushed design.
At close ranges upon impact, the Fusion will often fail to impart any measure of hydrostatic shock and game can appear quite unaffected by well placed shots. After impact on medium game, the bullet expands, produces a quite normal wound channel (similar to other 7mm 140 grain bullets) while gradually breaking down until very little is left of the original projectile. The broken off fragments tend to be small, often less than 1mm (40 thou) in diameter. To this end, the Fusion is neither a fast killing or deep penetrating projectile. The 140 grain TSX is undoubtedly a deep penetrating projectile, able to take a 1200lb animal broadside, although, such a practice should be considered unethical due to the small diameter of the wound. Nevertheless, this bullet is the best choice in the 7mm08 for tough game weighing between 90 and 320kg (200-700lb).
On lighter medium game, the TSX is a little too stout for all around work. This does not mean that the Barnes does not readily expand, to the contrary, wounding through vitals is ideal. The only problem with using this projectile on lighter game is that the trauma does not also occur immediately upon impact or during exit wounding. Kills at impact velocities below 2600fps and especially below 2400fps can be very slow as a result. If the TSX is to be used on lighter medium game, bullets should be placed to break major bones and locomotive muscles in order to effect immediate incapacitation.
Federal’s heavy weight load for the 7mm08 utilizes a proprietary 150 grain Speer Hotcor bullet with a cannelure, a design feature which is not normally available to hand loaders. This is one very good medium game loading. The Speer opens up quickly on impact, produces a wide wound channel before expansion is arrested by the cannelure. Penetration is slightly better than the Fusion load which costs twice the price of the budget branded Hotcor loading and is on par with the Partition and Accubond loads.
Winchester produces two loads for the 7mm08, the 140 grain Power Point at 2800fps and the 140 grain Ballistic Silvertip at 2770fps.
Both are humble performers offering rapid expansion but limited penetration. Hornady currently list two Superformance loads. These include the 139 grain SST at 2950fps and the 139 grain GMX at 2910fps. Like the former Light Magnum loadings, the Superformance ammunition gives ‘true to advertised’ velocities in 24” barrels. As is almost always the case, shorter barrels lose 35fps per inch of barrel removed. In standard 22” sporter barrels, the SST at 2890 is slightly faster than Federal loads and also slightly faster than can normally be achieved with hand loads.
The 139 grain SST is very hard hitting out to 250 yards (2400fps), producing a wide, violent wound. Penetration is reasonably good at impact velocities above 2600fps (150 yards) due to the swaging/forming a uniform mushroom, although the 139 grain SST is unsuitable for tail on shots on light bodied game.
At longer ranges, the 7mm 139 grain SST projectile is prone to suffer jacket core separation however cross body and quartering wounding is usually more than adequate.
The GMX is, like the Barnes TSX, is better suited to heavier animals above 90kg (200lb) as opposed to all around use, simply because on light game, even though wounding can be broad, the delay in killing can lead to difficulty tracking dead run game.
http://www.ballisticstudies.com/Knowledgebase/7mm-08+Remington.html
