Introduction
Bullet construction plays a crucial role in terminal performance. Over the years, I’ve researched, tested, dissected, and documented many designs to better understand how jacket thickness, tip design, cavity depth, and ogive geometry influence expansion and penetration. This updated write-up consolidates my earlier notes with recent measurements and cross-sections, structured more objectively for clarity.
I first began using Hornady AMAX bullets for long-range hunting. While not marketed for hunting, they performed exceptionally well for me. Later, I noted that:
Terminally, the ELD-X is essentially an improved SST, while the ELD-M is an improved AMAX.
About 4–5 years ago I began experimenting with the Sierra Tipped MatchKing (TMK). I was impressed with its accuracy and balance between expansion and penetration. Compared with Hornady’s match bullets:
All bullets were sectioned with an end mill and measured with digital calipers. Jacket thickness values are taken at the base unless otherwise noted; ogive thickness was measured at the forward curve. Meplat diameters were measured directly, and cavity depths were tested with calipers or needle probes.
Below is a condensed summary of representative measurements (grouped by brand).
Hornady
Meplat width and cavity depth heavily influence impact behavior. Larger meplats and deeper cavities weaken the ogive, enhancing expansion and fragmentation. Slender ogives with small openings may resist deformation, especially with thicker jackets. For consistent fragmentation below 1600 fps, a meplat of ~.100" is ideal, though this reduces BC. A .070" meplat can balance long-range BC with wounding potential.
Bullet construction is not static — each brand and line features distinct design choices that impact both external and terminal ballistics. Understanding jacket thickness, ogive taper, tip material, and cavity depth allows hunters and shooters to make more informed bullet selections.
For those interested in the complete dataset with all measurements, a reference table is available as an Excel and PDF attachment at the bottom of this thread.
Bullet construction plays a crucial role in terminal performance. Over the years, I’ve researched, tested, dissected, and documented many designs to better understand how jacket thickness, tip design, cavity depth, and ogive geometry influence expansion and penetration. This updated write-up consolidates my earlier notes with recent measurements and cross-sections, structured more objectively for clarity.
Hornady AMAX, SST, ELD-M, and ELD-X
I first began using Hornady AMAX bullets for long-range hunting. While not marketed for hunting, they performed exceptionally well for me. Later, I noted that:
- The SST has a cannelure, interlock ring, and older polymer tip (which was prone to melting and degrading BC).
- The ELD-X uses Hornady’s improved Heat Shield tip, has an interlock ring but no cannelure (increasing accuracy potential), and features a jacket tapering from thick base to thinner ogive.
- The AMAX and ELD-M share very thin, uniform jackets (~.024"), lack bonding rings, and therefore expand reliably at lower velocities (~1300 fps).
Terminally, the ELD-X is essentially an improved SST, while the ELD-M is an improved AMAX.
Sierra TMK and Other Designs
About 4–5 years ago I began experimenting with the Sierra Tipped MatchKing (TMK). I was impressed with its accuracy and balance between expansion and penetration. Compared with Hornady’s match bullets:
- TMK jackets average ~.026", slightly thicker than ELD-M.
- Larger meplats and deeper cavities under the tip help ensure reliable expansion down to ~1400 fps.
Measurement Methods
All bullets were sectioned with an end mill and measured with digital calipers. Jacket thickness values are taken at the base unless otherwise noted; ogive thickness was measured at the forward curve. Meplat diameters were measured directly, and cavity depths were tested with calipers or needle probes.
Sample Measurements by Manufacturer
Below is a condensed summary of representative measurements (grouped by brand).
Hornady
- A-Tip (.308, 250gr): Jacket .0240", Meplat .1255"
- A-Tip (.338, 300gr): Ogive .0260", Base step .0320", Above step .0270", Meplat .1265"
- A-Tip (.284, 190gr): Jacket .0270", Ogive .0220"
- AMAX / ELD-M: Jacket .0240"
- ELD-M (208gr): Ogive .0160"
- V-MAX: Ogive .0170", Meplat .0910"
- ELD-X: Ogive .0230"
- Interlock SP: Jacket .0370"
- Ballistic Tip: Ogive .0235", Base .0510", Boat-tail transition .0645", Actual base .1370"
- TMK: Jacket .0255"
- BlitzKing: Ogive .0170", Base .0220", Meplat .1300"
- HP GameKing: Jacket .0280", Ogive .0250"
- HP GameKing (25cal): Meplat .0630"
- TGK (Tipped GameKing): Jacket .0460"
- MatchKing (77gr, .224”): Base .0215", Ogive .0260"
- MatchBurner: Jacket .0270", Meplat .0270"
- Hybrid: Jacket .0265", Ogive ribbing .0310"
- Bondstrike: Meplat .1185", Ogive .0300", Base .0490"
- Tipstrike: Meplat .0900", Base .0455"
- Scirocco II (25cal): Jacket .0645", Ogive .0355"
- Core-Lokt RN: Ogive .0240", Ogive .0270", Base .0375"
- RBAT (210gr): Jacket .0220", Ogive .0180"
- 213gr: Jacket .0240", Meplat .0455"
- Terminal Shock (125gr): Jacket .0260"
The Role of Meplat and Cavity
Meplat width and cavity depth heavily influence impact behavior. Larger meplats and deeper cavities weaken the ogive, enhancing expansion and fragmentation. Slender ogives with small openings may resist deformation, especially with thicker jackets. For consistent fragmentation below 1600 fps, a meplat of ~.100" is ideal, though this reduces BC. A .070" meplat can balance long-range BC with wounding potential.
Conclusion
Bullet construction is not static — each brand and line features distinct design choices that impact both external and terminal ballistics. Understanding jacket thickness, ogive taper, tip material, and cavity depth allows hunters and shooters to make more informed bullet selections.
Appendix
For those interested in the complete dataset with all measurements, a reference table is available as an Excel and PDF attachment at the bottom of this thread.
Instagram
YouTube
Facebook