The importance of following the manufacturers' instructions

Bullet design is a highly scientific exercise which requires in depth knowledge and understanding of the different ballistic areas known as internal, external and terminal ballistics.

The resources required to achieve the utmost best in bullet design are widely spread. These resources include, but are not limited to, background and pre-decision intelligence, years of applicable experience and observation of actual result, suitable material definition and knowledge, standard and specification evaluations, R&D, laboratary services when needed, purchasing services, manufacturing control, quality assurance and finally experience based recommendations being made available to users.

GS Custom as a highly successful designer and manufacturer of one of the world's best monolithic bullet ranges, has all the above in place and very neatly put together on their website.

Having taken all the trouble to put the above in place, it is very little asked by the manufacturer of GS Custom bullets, that users should follow the few simple instructions to allow themselves to achieve the best intended for them, through the use of their premium grade bullets.

HV , FN and SP Bullets Reloading Data and Guidelines


The unique construction of HV, FN and SP Bullets allows the reloader to achieve higher speeds with a given weight of bullet than what was previously possible. Terminal ballistics of HV and FN bullets improve with additional speed. The exception would be if you require only standard speeds and want to reduce recoil. HV, FN and SP bullets work at lower pressure levels and therefore reduce recoil at standard speeds. Internal ballistics are superior with HV, FN and SP bullets in all cases. Follow the guidelines below for optimal performance with HV, FN and SP bullets.

Use an HV, FN and SP bullet that is recommended for the calibre. The correct length of bullet for the rate of twist and case capacity of the cartridge is more important than the weight.

HV, FN and SP bullets do not raise pressure levels like jacketed lead and standard and grooved monometal bullets do, when seated against the rifling.

Develop the speed of your load first. Once the desired speed is achieved, then tune the accuracy of the grouping by experimenting with overall cartridge length. Trying to do both at the same time will require more bullets than separating the two elements. See the load data page for detail.


Do not use the load data for any other type of bullet.
This data only applies to GS Custom HV bullets.

See the Technical Data page for assistance with the correct choice of bullet and for BC values.

The load data tables represents data collected from internal ballistics software, pressure test data from certified laboratories and load data developed by us. Start loads can be used in any rifle in good condition but the MAX FPS number must never be exceeded and must be approached as all maximum load data is approached - with caution and with checks for signs of pressure.

1. These loads are based on a barrel length of 24" (610mm). The MAX FPS can be adjusted by the FPS / Inch (25.4mm) value for barrels that are longer or shorter than 24"

2. MAX FPS means that this speed must not be exceeded after adjustment with the FPS / Inch value.

3. Always use a magnum primer with drive band bullets. See the reason. Do not crimp drive band bullets. See the reason.

4. Use the propellant recommended by the manufacturer in the load data tables. See the reason.

5. If the MAX FPS column contains CC after the speed, it means that case capacity will be the limiting factor and not the MAX FPS.

6. Bullet numbers consist of the caliber (224) the weight (35gr) the bullet type (HV) and the part number (058)

7. Should you need any information regarding load development and suitability for specific calibres - which are not to be found on this page - please send us an e-mail via the applicable CONTACT US page on our website.

Load Procedure:
* Start-loads in the load data table may produce maximum f.p.s. in some rifles. Develop loads with a chronograph.

* Develop speed first by loading two cartridges at the start load and two each increasing in half grain increments. Use one grain increments if the bullet is over 100 grains. The indicated maximum speed in the load data table, after adjustment with the FPS/INCH number, will closely correspond to the maximum pressure allowed for that caliber. The powder load required to reach the MAX FPS will differ from rifle to rifle.

* To start, load the bullet with two drive bands in the case neck. Check if this cartridge overall length (col) will fit in the magazine box of the rifle. If it does not, seat the bullet deeper until the cartridge fits the magazine. Check if the col will allow the cartridge to chamber. If it does, continue with powder load development. HV and FN bullets do not cause pressure spikes when loaded touching the rifling. See the reason for this.

* Once the desired speed is reached, load 15 rounds with that powder charge and at the maximum cartridge length possible in the rifle.

* Fire three for group. Seat the next three 0.5mm (0.02") deeper and fire for group. Repeat the process until the best group is obtained. Use 1.0mm (0.04") steps if the bullet is over 100 grains.

* If pressure signs occur at substantially lower speeds than the maximum f.p.s. indicated, try a propellant that is more bulky in order to reduce air space in the case and make sure a magnum primer is used. If pressure signs are still present at low speeds, have the the rifle checked for headspace, out of specification chamber size and correct bore and groove dimensions.

General rules given above will also apply to SP and FN bullets.

Any specific guidlines for SP and FN bullets will be found on the pages for SP and FN bullets.

We receive feedback from customers on a regular basis telling us that they have followed the easy instructions carefully and the results are astounding!

If at any time you require more information or assistance, send us an e-mail via our CONTACT US page applicable.

"It is human nature to think wisely and act foolishly." ~ Anatole France.